- Copy stable/10 (r259064) to releng/10.0 as part of the
10.0-RELEASE cycle.
- Update __FreeBSD_version [1]
- Set branch name to -RC1

[1] 10.0-CURRENT __FreeBSD_version value ended at '55', so
start releng/10.0 at '100' so the branch is started with
a value ending in zero.

Approved by: re (implicit)
Sponsored by: The FreeBSD Foundation

Copy head (r256279) to stable/10 as part of the 10.0-RELEASE cycle.

Approved by: re (implicit)
Sponsored by: The FreeBSD Foundation

Some objects - such as *_genassym.o are not hooked into
SRCS OBJS or anything else, yet have a dependency on symlinks
such as machine/

Reviewed by: obrien

Remove the links: target. It too is homelessly outdated since it
relies on the outdated defines list. It likely hasn't been useful in
15 years, and certainly not in the last decade.

MFP4 change 214967:
Make the process of embedding MDROOT images less perilous by
makeing the target that links kernel and embedding the image
depend on the image. This means, if the image doesn't exist you
find out before you try to boot from it and that if you change
the image you don't have to touch some random source file to
cause a rebuild.

Don't hide that we're embedding the image.

Revert r222186 per instructions for FreeBSD 10.
(a 10-CURRENT share/mk is already required to build a 10-CURRENT kernel
on 9-STABLE)

Unfortunately the change in r237958 resulted in s/install/instclean/ due to
the aggressive pattern matching of the :C modifier. I tested build and
install in 2 phases, however with different solutions, resulting in the
breakage. Mea culpa.

The solution is to break out the all: target. This causes a few lines of
code duplication, but now the all: target works as it should, and the
other targets continue to work as they did before.

While I'm here, add a ===> header line to the start of each port build
to make it easier to find/more clear in the logs.

For the ports modules building code, clean WRKDIR before building. This is
important for those that use -DNO_CLEAN routinely, since it will prevent
installing stale stuff, and even more important when the port is upgraded
to a newer version. When the user doesn't use -DNO_CLEAN, this will create
an infinitesimal amount of extra work, but won't hurt anything.

This is necessary because the ports tree has flags that prevent the ususal
'update the build if newer source files exist' logic from doing what it
would do in the base.

Improve the functionality of the PORTS_MODULES knob by adding
LOCALBASE/bin and sbin to PATH, allowing dependencies to be found;
adding SRC_BASE and OSVERSION to match the new kernel, and putting
the related builds under MAKEOBJDIRPREFIX so that they only need
to be built once per kernel.

In addition to the PR this includes ideas/contributions from crees
and matthew.

PR: ports/161452
Submitted by: Garrett Cooper <yanegomi@gmail.com>

Allow (with a license warning) "options ZFS" to work in static kernels.

The 'make depend' rules have to use custom -I paths for the special compat
includes for the opensolaris/zfs headers.

This option will pull in the couple of files that are shared with dtrace,
but they appear to correctly use the MODULE_VERSION/MODULE_DEPEND rules
so loader should do the right thing, as should kldload.

Reviewed by: pjd (glanced at)

- CTF knob is now implemented using common scheme: MK_CTF=yes/no is
defined based on WITH/WITHOUT_CTF settings, default is WITHOUT_CTF,
NO_CTF overrides WITH_CTF (used by Makefile.inc1)
- CTFCONVERT_CMD/NORMAL_CTFCONVERT are now defined to empty string
if make(1) can handle empty commands

- fix WITH_CTF when specified in /etc/src.conf [1]
- CTFCONVERT_CMD=... is a hack (should be defined to empty string instead):
make(1) should be taught to ignore empty commands silently in compat mode
(as it does in !compat mode, GNU make also silently ignores empty commands)
and to skip printing empty commands in !compat mode
- config(8) should generate ${NORMAL_CTFCONVERT} invocation without '@':
this will allow to simplify kern.pre.mk even more and lessen the number
of shell invocations during kernel build when CTF is turned off
- WITH_CTF can now be converted to usual MK_CTF=yes/no infrastructure

Pointy hat to: fjoe [1]

Conditionalize ctfconvert/ctfmerge runs on make level (.if/.endif) instead
of executing a shell on every object or executable/library file.

This shaves off more than 30,000 shell invocations during buildworld.

Test against "no" rather than "yes" for MK_KERNEL_SYMBOLS
Also, change DEBUG back to DEBUG_FLAGS in kmod.mk. The latter accidentally
snuck in with my backwards compat fix.

Submitted by: ru,gcooper

Backwards compatibility hacks to allow kernels to be built via config
wihtout updating world (good transition aide for -current, but also
allows kernels to be built on -stable the old way too). This likely
should go away around FreeBSD 10.0 or so.

Start to usher INSTALL_NODEBUG hack out the door. Add new
WITH{OUT,}_KERNEL_SYMBOLS (defaulting to WITH). In the fullness of
time, likely around 2020, INSTALL_NODEBUG will be removed. For now,
don't print a warning when using INSTALL_NODEBUG, but that will be
coming soon.

Add an x86/include directory to the kernel to hold headers that are common
to amd64, i386, and pc98. The headers are installed to /usr/include/x86
during an installworld, and an 'x86' symlink is created for kernel builds
similar to 'machine' so that the headers can be included as <x86/foo.h>.

Reviewed by: imp

MFtbemd:

Prefer MACHNE_CPUARCH to MACHINE_ARCH in most contexts where you want
to test of all the CPUs of a given family conform.

Convert several instances of MACHINE_ARCH to MACHINE_CPUARCH and use the
correct compiler flags on 64-bit PowerPC.

WITH_CTF can now be specified in src.conf (not recommended, there
are some problems with static executables), make.conf (would also
affect ports which do not use GNU make and do not override the
compile targets) or in the kernel config (via "makeoptions
WITH_CTF=yes").

Additional (related) changes:
- propagate WITH_CTF to module builds
- do not add -g to the linker flags, it's a noop there anyway
(at least according to the man page of ld)
- do not add -g to CFLAGS unconditionally
we need to have a look if it is really needed (IMO not) or if there
is a way to add it only when WITH_CTF is used

Note: ctfconvert / ctfmerge lines will not appear in the build output,
to protect the innocent (those which do not build with WITH_CTF would
see the shell-test and may think WITH_CTF is used).

Reviewed by: imp, jhb, scottl (earlier version)
Discussed on: arch@

Propagate CONF_CFLAGS (from makeoptions) to the module build too.

Discussed with: jhb (on arch@)

Always compute the root of the kernel source tree and explicitly pass it
to module builds. This avoids having to have the module builds walk up
the tree to find the kernel sources. It also allows a kernel + module
build to succeed when a new level of module subdirectories is added without
requiring that the /usr/share/mk/bsd.kmod.mk file on the machine be patched.

MFC after: 1 week

Using KMODOWN/KMODGRP rather than hard coding root/wheel for
installing the kernel allows one, like with modules, to override
the default user/group and install as non-su to a temporary
directory to test, create images or seed a tftp dir.

Reviewed by: Andrzej Tobola <ato@iem.pw.edu.pl>
MFC after: 4 weeks

Add CTF conversion to the objects compiled from generated code.
This allows DTrace scripts to access variables like 'ostype'.

Add support for generating CTF data for the kernel.

Introduce a standalone shell script for embedding MFS image.

This allows to fix a problem with ARM kernel.bin not having the MFS image
embedded: it is objcopied from the kernel.noheader temporary ELF file, which
was not subject to embedding the MFS image previously.

Reviewed by: imp
Approved by: cognet (mentor)

If KERNEL_EXTRA is defined, make kernel-all target depend on it.
If KERNEL_EXTRA_INSTALL is defined, install it into ${DESTDIR}${KODIR}.

now that MFS_IMAGE is in the FULLKERNEL section, use FULLKERNEL instead of
KERNEL_KO, this fixes MFS_IMAGE on a debugging kernel...

Submitted by: Neelkanth Natu

MF kmod.mk 1.176: Properly handle vnode_if.h dependencies.

Instructed by: bde

- Remove include links only when .depend is also removed, so that
"make depend; make clean; make -n" works.

- Preseve kernel's .depend if it already exists and its creation
is interrupted.

Reported/reviewed by: bde

Don't use touch when what is really meant is :> (create an empty file, or
truncate it if it exists) or :>> (ensure the file exists, but don't change
it if it already does)

Reviewed by: ru
MFC after: 2 weeks

Remove the insistance on having a device.hints. This was a seat belt
for those upgrading from 4.x -> 5.x. It is therefore no longer
necessary because it is installed on 5.x and 6.x and one has to
upgrade from 6.x -> current, or at the very least 5.x (although not
supported, it can be made to work).

Handle MFS_IMAGE in the ${FULLKERNEL} target, so that we can build kernel
with MFS root without debugging.

add support for makeoptions MFS_IMAGE="<file>" in the config file which
will automaticly populate the kernel w/ the mfs image...

Remove .depend when doing "make cleandir".

I couldn't find any traces of what the tags1 file was supposed to do.

Teach this to create the "machine" and ${MACHINE_ARCH} (for pc98
only now) symbolic links in the kernel compile directory, rather
than relying on config(8) to do this. (The changes to config(8)
will be committed separately.) This is aimed towards making the
config(8) as lightweight as possible.

Idea by: bde (all bugs are mine)

Rename the .dbg extension to .symbols, which matches "symbol-file"
gdb(1) command better, though I must admit it's confusing: these
files have not only [debugging] symbols, but much more than that.

Requested by: obrien

Use ${S} to pass ${SYSDIR} to ports. This makes PORTS_MODULES
feature work when compiling a kernel via "make buildkernel".

Noticed and tested by: nork

Installing debug modules was a bad idea -- I bogusly assumed that
our kernel linker will only load PT_LOAD segments, apparently not.
Instead, produce .dbg objects from .debug objects, and install
them together with non-debug objects, as described in objcopy(1).

Original code by: obrien

Refactor (some more) installation of kernel and module objects.

Try to make everyone happy: David (to have debug kernels installed
by default), Warner (to be able to override that), and myself (for
actually making it all work and to be consistent).

Now, if kernel was configured for debugging (through DEBUG=-g in
the kernel config file or "config -g"), doing "make install" will
install debug versions of kernel and module objects with their
canonical names,

kernel.debug -> /boot/kernel/kernel
if_fxp.ko.debug -> /boot/kernel/if_fxp.ko

Installing a kernel not configured for debugging, or debug kernel
with INSTALL_NODEBUG variable defined, will install non-debug
kernel and module objects.

Also, restore the install.debug and reinstall.debug targets that
are part of the existing API (they cause some additional gdb(1)
scripts to be installed).

Back out most of 1.84. It was unwise to force debug kernels to always
be installed. It should have been optional to install a non-debug
one, just like it was formerly optional to install a debug one. In
order to do that, most of 1.84 had to go.

Instead, make installing the debug kernel the default, but create a
new option INSTALL_NODEBUG for those people that have small /
partitions and good source control habits.

This preserves the behavior of 1.84 while allowing it to be overriden
for people (like me) that do not have the time to upgrade to get a
bigger / and also don't have time for stupid makefile tricks when
upgrading their older system, but still want a kernel.debug around if
things go south.

For HEAD, install a kernel with debug information if DEBUG is a kernel
config option. It is too easy to loose the build directory and not have
symbols for kgdb to read.

Don't build PORTS_MODULES if NO_MODULES is defined

Install ports defined in PORTS_MODULES at make reinstall time too.

Reviewed by: imp

Be resistant to DESTDIR being set to some unkosher value, e.g. "/".

Noticed by: Steve Ames

Clean all generated vnode_if* files.

Fix "make depend" to not redundantly rebuild the .depend file.

Reviewed by: bde (I think so)

Now that we have proper links, no need to fake up ones as part of
depend. Now that we no longer need this hack, remove it.

Forgotten by: imp
Reminded by: nyan

Don't generate major.c anymore.

Get SYSDIR set correctly for building ports.
On install, do deinstall reinstall

use __target in preference to target

Back when VOP_* was introduced, we did not have new-style struct
initializations but we did have lofty goals and big ideals.

Adjust to more contemporary circumstances and gain type checking.

Replace the entire vop_t frobbing thing with properly typed
structures. The only casualty is that we can not add a new
VOP_ method with a loadable module. History has not given
us reason to belive this would ever be feasible in the the
first place.

Eliminate in toto VOCALL(), vop_t, VNODEOP_SET() etc.

Give coda correct prototypes and function definitions for
all vop_()s.

Generate a bit more data from the vnode_if.src file: a
struct vop_vector and protype typedefs for all vop methods.

Add a new vop_bypass() and make vop_default be a pointer
to another struct vop_vector.

Remove a lot of vfs_init since vop_vector is ready to use
from the compiler.

Cast various vop_mumble() to void * with uppercase name,
for instance VOP_PANIC, VOP_NULL etc.

Implement VCALL() by making vdesc_offset the offsetof() the
relevant function pointer in vop_vector. This is disgusting
but since the code is generated by a script comparatively
safe. The alternative for nullfs etc. would be much worse.

Fix up all vnode method vectors to remove casts so they
become typesafe. (The bulk of this is generated by scripts)

Use PORTSDIR, falling back to /usr/ports

Ports aren't generally ready for parallel make.

Pointed by: Ben Mesander

PORTS_MODULES: a list of ports to build with this kernel.

# I directly use the targets for building this, but it was suggested
# to use portupgrade. I couldn't fit that into the target model, so I
# punted.

Per recent HEADSUP: Disconnect (old)vinum from the kernel build.

Users should move to the new geom_vinum implementation instead.

The refcount logic which is being added to devices to enable safe module
unloading and the buf/vm work also in progress would require a major rework
of the (old)-vinum code to comply with the new semantics.

The actual source files will not be removed until I have coordinated with
the geomvinum people if they need any bits repo-copied etc.

Pass the idea of the make(1) binary to use down to newvers.sh.
This is necessary so source upgrades use the correct binary.

MFC after: 3 days

For the record: Problem spotted by Scott Long, who mentioned
that source upgrades from 4.7 to recent 5.x and 6.0 are broken.
Detailed analysis shows that 4.7 has a broken make(1) binary.
A breakage was fixed in RELENG_4 in make/main.c,v 1.35.2.7 by
imp@, though the commit log erroneously stated "MFC 1.68"
while in fact it should have been spelled as "MFC 1.67".

We don't need GEN_M_CFILES. Fold it into GEN_CFILES definition and
adjust as necessary.

Suggested by: bde

MFp4:

Now that the devs files are marked before-depend, we can remvoe them
from a few places they were explicitly mentioned (along with
BEFORE_DEPEND).

Noticed by: bde

Add pccarddevs.h and usbdevs.h as depends, ala miidevs.h, in the right
places. This should have been committed last night with the rest of
my changes, but wasn't.

Pointy hat to: imp

Use ' rather than ".

Submitted by: ru

Quote NM in case you need to force it to something with args.

Submitted by: jmallett

Don't make having ${DESTDIR}/boot/device.hints a prerequisite to
installing a kernel on ia64.

Merged from kmod.mk,v 1.152: strip debugging symbols even when not
configured for debugging. This saves some bytes, and produces the
same "kernel" object as if it was configured for debugging.

Attempt to clean up the emu10k1-alsa.h stuff so that config doesn't
delete it each time its run and have it regenerated each time by make.
I used a quick hackish script rather than putting it in the files file
and used the before-depend rule to avoid the depend/no-depend hacks.

The gdbinit.${MACHINE_ARCH} script may not exist.

Add emu10k1-alsa%diked.h dependancies.

Define KERNBUILDDIR again. The RELENG_5_2 tree is stable enough that
we can turn this back on to start to resolve the issues with the
release process.

Approved by: scottl

Backed out rev.1.48. -Winline now works better so there should be no
need for a hack to prevent bogus warnings about unused inlines.

Garbage-collected some vestiges of objformat support (mainly ${FMT}).

Fixed some style bugs (manly a few English usage errors in comments and
many unusual indentations for continued lines in code).

gdbinit target: Remove comment lines from dot.gdbinit. This allows us to
put dire warnings in the original and not find them in the installed version.

Turns out that building modules with the kernel opt files is
uncovering some interesting problems. Be conservative and effecitvely
disable this by default. Interested parties may still define
KERNBUILDDIR by hand to achive the same effect.

I plan on referting this change after 5.2 is released, or sooner if
the issues with building releases are resolved and re@ approves.

Approved by: re@ (scottl, marcel)

Moved $FreeBSD$ to the beginning of the file.

Improved wording in a nearby comment.

Include opt_global.h in the modules build, when building from a normal
kernel build. This makes it possible for me not to get pissed off that
random.ko crashes the system trying to rdtsc() when the i386/cpu.h
support code decides it's okay to call that op when neither I386_CPU or
I486_CPU is defined. I guess it also makes WITNESS/INVARIANTS defines
get picked up by the modules.

Add a "-f" flag for asf(8) which performs a search to find the each module
no matter where in the directory structure it may be. Use this and the "-k"
flag in the generated gdbinit files so that the "getsyms" function in gdb
requires no user intervention to run and will find every module if they're
in the kernel build's module directory. This is still quite useful for
cases where gdb knows that the path for some modules is /boot/kernel and
others are in the object directory for /usr/src/sys/$ARCH/compile/kernel.

Approved by: grog

Fix logic in Makefile.i386,v 1.249: only back up ${DESTDIR}${KODIR}
to ${DESTDIR}${KODIR}.old if we have booted from ${DESTDIR}${KODIR},
and always keep kern.bootfile in a good shape.

Don't complain about inlines for genassym

Protect against .depend file somewhere else in the .PATH.
Also consolidate building rules for special files.

Some glue to allow lint(1) to work on the kernel. This is not
complete without some config(8) work. Config(8) needs to provide
some ${NORMAL_LINT} rules to make foo.ln files.

If we're building a debug kernel, add target to install the .gdbinit files
from tools/debugscripts.

Fix a style nit.

Submitted by: ru

Be sloppier about the miidevs.h dependency. This reduces the maintenance
effort at the expense of making miidevs.h a dependency for very .o.

Requested by: imp

If DESTDIR was specified as a makeoption in the kernelconfig file
we want to pass it on to the modules build so we don't install
the kernel under DESTDIR and the modules in /boot.

Help out with linting. Print the ${LINT} command line. This makes
the all-important -DFOO -IBAR options "hang out".

Leave the `clobber' target alone, it clobbers too much (including
the generated Makefile) to be useful as the cleandir replacement.

Reported by: des

Abuse `cleandir' for what `clobber' was supposed to do, for peter.

Hopefully, obviate the need of ``make depend''.

Initiate the de-orbit burn sequence for <bsd.kern.mk>.
Always use sys/conf/kern.mk when building kernel/modules.
<bsd.kern.mk> is only preserved for sys/boot/pc98/boot2
for now, but this will be fixed. If there are other
users of <bsd.kern.mk>, please let me know.

Reminded by: bde

Standardize handling of locore.[sS] etc. files.

Submitted by: jake, bde, ru

Add necessary awk magic to create a table of major numbers allocated
in conf/majors so we can avoid autoallocating them in the kernel.

Overhaul the targets and hope this is now much more readable.

This adds some orthodox kernel-* and modules-* targets and
retires harmful ``clobber''.

Now, do we really want to keep the ``modules'' target here?

Move the miidevs.h build stuff to conf/files so that config(8) doesn't
clobber it each time.
XXX: maybe this should be 'optional miibus' rather than 'standard'

Remove miidevs.h and generate it from miidevs at compile time.
The devlist2h.awk tool to do this has been repocopied to sys/tools/.

Hook the aic7xxx modules up. This requires some extra care since aicasm
is a compiler tool and needs to be compiled by the host compiler. I've
tested this in i386->sparc cross-build, 4.7->current upgrade, normal
buildkernel target, and normal /sys/i386/compile/GENERIC configurations.

Submitted by: ru

Don't show the command line when doing "make lint".

Initiate deorbit burn for the i386-only a.out related support. Moves are
under way to move the remnants of the a.out toolchain to ports. As the
comment in src/Makefile said, this stuff is deprecated and one should not
expect this to remain beyond 4.0-REL. It has already lasted WAY beyond
that.

Notable exceptions:
gcc - I have not touched the a.out generation stuff there.
ldd/ldconfig - still have some code to interface with a.out rtld.
old as/ld/etc - I have not removed these yet, pending their move to ports.
some includes - necessary for ldd/ldconfig for now.

Tested on: i386 (extensively), alpha

Added rules to generate .c files from .m files. Run mkdep on these .c
files. This fixes at least "make" (without -j) after "make clean".

Finished removing env(1) commands, as in rev.1.13 but non-broken. Set
the environment for the last command of the pipeline (xargs) instead
of too early in the broken version or using an extra env process for
each command spawned by xargs as in rev.1.12. Fixed a nearby English
error.

Spell kenrel as 'kernel' for consistency with the rest of the universe.

Inspired by: bde

Remove duplicate 'modules-tags' rule

Moved the rule for locore.o from kern.post.mk to Makefile.$ARCH.

Drop support for COPY, -c has been the default mode of install(1)
for a long time now.

Approved by: bde

s/install -c/${INSTALL} ${COPY}/

Quick fix for high resolution kernel profiling on i386's. Use
-finstrument-functions instead of -mprofiler-epilogue. The former
works essentially the same as the latter but has a higher overhead
(about 22 more bytes per function for passing unused args to the
profiling functions).

Removed all traces of the IDENT Makefile variable, which had been
reduced to just a place for holding profiling's contribution to CFLAGS
(the IDENT that gives the kernel identity was renamed to KERN_IDENT).

Fixed broken ``make -jX install''.

Spotted by: make release TARGET_ARCH=ia64

sysctl -w -> sysctl

Add a dummy cleandir target to the kernel section so that make buildkernel
actually works on a kernel config with NO_MODULES set.

Use makeobjops.awk rather than makeobjops.pl.
(with big thanks to Oliver Fromme <olli@fromme.com>)

The install.debug and reinstall.debug targets are needed solely
to build kernel and kernel modules so stop supporting them in
bsd.subdir.mk and reimplement them in kern.post.mk and kmod.mk
as special versions of the install and reinstall targets, and
only define them if DEBUG is also defined (when debug versions
are really built).

Prompted by: bde

Minor cleanups to post.mk from bde. Mostly ordering

Backed out the part of the previous commit related to xargs. It just
broke things, since "name=value ... cmd ..." only works for simple
commands (not for pipelines).

Removed env(1) commands. make(1) uses a real shell, and
"env name=value ... cmd ..." is just a pessimized way of doing
"name=value ... cmd ..." in real shells. Set the environment
(without using env(1)) before starting xargs so that env(1)
is not needed in "xargs env name=value ... cmd ..."

lint the previous lint commit.

Reviewed by: markm

Allow "make lint" to mostly work. Our sources are very unclean WRT
lint, so this is turned off by default. Setting WANT_LINT will turn
on generation of lint libraries for /usr/libdata/lint/*.ln.

Reviewd by: silence in -audit.

Use vnode_if.awk rather than vnode_if.pl

Don't echo a comment during make depend.

Use make -V VARIABLE | xargs ... to pass argument lists to program
so that this is safe even if VARIABLE is longer than kern.argmax.

There is another instance of CFILES which might need the same treatment,
and might be noticed when doing a "make links".

The same has to be done in RELENG_4 (on some different file).

Noticed-by: picobsd cross-compiling LINT
Suggested-by: Alfred (bright@mu.org), des@freebsd.org
MFC-after: 3 days

Eliminate the use of commons in the kernel and modules,
simplifying the module linking process and eliminating the risks
associated with doubly-defined variables.

Cases where commons were legitimately used (detection of
compiled-in subsystems) have been converted to use sysinits, and
any new code should use this or an equivalent practice as a
matter of course.

Modules can override this behaviour by substituting -fno-common
out of ${CFLAGS} in cases where commons are necessary
(eg. third-party object modules). Commons will be resolved and
allocated space when the kld is linked as part of the module
build process, so they will not pose a risk to the kernel or
other modules.

Provide a mechanism for controlling the export of symbols from
the module namespace. The EXPORT_SYMS variable may be set in the
Makefile to NO (export no symbols), a list of symbols to export,
or the name of a file containing a newline-seperated list of
symbols to be exported. Non-exported symbols are converted to
local symbols. If EXPORT_SYMS is not set, all global symbols are
currently exported. This behaviour is expected to change (to
exporting no symbols) once modules have been converted.

Reviewed by: peter (in principle)
Obtained from: green (kmod_syms.awk)

s/oferride/override/

submitted by: dima

Move initialization of the MKMODULESENV envorinoment to kern.pre.mk
from kern.post.mk so port makefiles can augment it.

Submitted by: nyan

Move all: target to kern.pre.mk so it matters less where you include
kern.post.mk.

# this should allow us to move kern.post.mk to the last line of the makefiles,
# but I'll do that slowly as I verify that one can do that w/o breaking things.

Submitted by: naddy

Move machine link creation from genassym to kernel-depend, per nyan@

Arrgh. A clean pc98 build failed due to bogons on my part :-(.

Fix it by putting back the link of machine to sys/i386/include rather
than ../../include (aka sys/pc98/include). I had a stale machine link
on my first test.

Not sure what the "right" fix is, but this unbreaks things.

Factor the common parts of the Makefile.foo files. This introduces two
new files: kern.pre.mk, which contains most of the definitions, and
kern.post.mk, which contains most of the rules.

I've tested this on i386 and pc98. I have had feedback on the sparc64
port, but no reports from anybody on alpha, ia64 or powerpc. I
appologize in advance if I've broken you.

Reviewed by: jake, jhb, arch@