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

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

Change <sys/diskpc98.h> to not redefine the same symbols that are
being defined in <sys/diskmbr.h>. Instead give the symbols here a
"PC98_" prefix. This way, both <sys/diskmbr.h> and <sys/diskpc98.h>
can be included in the same C source file.

The renaming is trivial. The only gotcha is that DOSBBSECTOR is
also redefined from 0 to 1. This because DOSBBSECTOR was always
used in conjunction with an addition of 1. The PC98_BBSECTOR symbol
is defined as 1 and the expression is simplified.

Note: it is not believed that ports are seriously impacted; or at
all for that matter.

Approved by: nyan@

Use the common PC98_SID_ACTIVE define instead of a local define.

Because there are so many more partitions on pc98 than on wintel (16
vs 4), supress all unused partition output unless -v is specified.
This makes operating on a 'typical' disk with one partition less
painful. The 30 lines needed for the empty partitions no longer
scroll the useful information off the screen. When the user requests
a specific partition, the unused information is not suppressed.

Also add the partition name to the -s output.

Initialize the partition name to 'FreeBSD' when -I is specified.

Fixes and new features:
o Merge the -I switch from i386 verison to initialize the partition table
to use the maximum amount possible for a single FreeBSD table.
o Improve warning when the geom method fails (which I think it
always will until geom_pc98 is updated to respond to this ctl message)
o when writing out the boot sector, we have to write out a minimum of
1024 bytes or the sector size. This is different than the i386 case where
we need to write out a minimum of 512 bytes (which is also the minimum
sector size). We already handle this difference on reading, but didn't
in writing, so attempting to write a new partition table would fail.
o Add MID to the -s output, since pc98 users are likely interested in
both of these parameters.

# I can now initialize disks on my pc98 machine either by -I or by
# manually entering the parameters. I don't know if fdisk -B works or not,
# since I'm not willing to risk my only working boot disk to test it..

Merged from src/sbin/fdisk/fdisk.c revision 1.81.
- Call gctl_free() to free resource allocated with gctl_get_handle().

MFC after: 3 days

Merged from src/sbin/fdisk.
- Attempt gctl verb "write MBR" when updating.

- Merged some missing changes from fdisk/fdisk.c.
- Remove ifdef PC98.
- Make WARN=4 clean.

Merged more changes from fdisk/fdisk.c.

Merged from src/sbin/fdisk/fdisk.c revision 1.77.

Merged from src/sbin/fdisk/fdisk.c revision 1.75.
(Don't prepend "/dev" if an argument given is an absolute pathname.)

Oops, DIOCGPC98 should be DIOCSPC98.

Merged from src/sbin/fdisk/fdisk.c revision 1.69.

MFi386: Use DIOCGPC98 ioctl.

Rename the dos_partition structure for pc98 to pc98_partition.

Fix typos, mostly s/ an / a / where appropriate and a few s/an/and/
Add FreeBSD Id tag where missing.

Merged various changes from src/sbin/fdisk/fdisk.c revisions up to 1.66.

Don't use DPCYL and DPSECT macros. These are not needed.

Submitted by: kawanobe@st.rim.or.jp (Kawanobe Koh)

Include <sys/diskpc98.h>

s/filesystem/file system/g as discussed on -developers

Add missing \ before an 'n' to get the proper newline when running
fdisk -s for each partition.

Add `_PATH_DEVZERO'.
Use _PATH_* where where possible.

Sync with sbin/i386/fdisk/fdisk.c revision 1.37.
(Don't try to open the /dev/rXXX device.)

Added PC98 version of fdisk.