Update dirdeps.mk et al

bmake-20240309 includes updates to dirdeps and meta mode makefiles

meta2deps.py: Fix a typo in a source code comment

- s/follwing/following/

MFC after: 3 days

Update meta mode makefiles

meta2deps - add checks to detect truncated/corrupted filemon data
(only known to happen on Linux hosts), to ensure we do not auto
update dependencies based on incomplete data.

meta.stage.mk adds STAGE_SHLIB_LINKS_FILTER and STAGE_LINK_AS_*

We also allow for hosts where egrep is deprecated for grep -E

Reviewed by: stevek

Update dirdeps.mk et al to 20211212 versions

dirdeps.mk: simplify computation of qualified vs unqualified dirdeps.
Note the importance of avoiding unresolved variables in DIRDEPS
Fix DIRDEP_LOADAVG_REPORT - expr(1) fails if expression evaluates to 0
Trim ${SRCTOP}/ from debug etc messages to make comparison easier.
Include number of DIRDEPS in debug output.
Trim ${SRCTOP}/ when exporting to env while building DIRDEPS_CACHE
to help avoid env exhaustion.
Use DIRDEPS_ALL_MACHINES_FILTER to better handle ALL_MACHINES
in complex build environments.

dirdeps-options.mk: use separate .undef for each variable

dirdeps-targets.mk: allow for '.' in DIRDEPS_TARGETS_DIRS

meta.autodep.mk: leverage ${.SUFFIXES} if we can.

meta.sys.mk: allow use in META_MODE vs DIRDEPS_BUILD

meta2deps.py: compute a list of dirdep extensions that map to current
TARGET_SPEC to avoid confusion.

Reviewed by: stevek

Update dirdeps.mk et al to latest

Move some local tweaks to local.*.mk

Reviewed by: bdrewery
MFC after: 1 week
Differential Revision: https://reviews.freebsd.org/D27300

Update dirdeps.mk et al to latest

dirdeps.mk and meta.autodep.mk will now look for
Makefile.depend.options
to handle optional dependencies, the work is all done by
dirdeps-options.mk

Also update to latest meta.stage.mk and gendirdeps.mk

Reviewed by: bdrewery
Differential Revision: https://reviews.freebsd.org/D15701

Fix syntax error in parse_path after r316952.

Also fix bad whitespace in sort_unique after r314809.

The parse_path syntax error came up in DIRDEPS_BUILD as the following
and emptied out all Makefile.depend files due to it:

# python share/mk/meta2deps.py
File "share/mk/meta2deps.py", line 538
rdir = os.path.realpath(dir)
^
IndentationError: unexpected indent

Sponsored by: Dell EMC Isilon

Latest version, we need to realpath anyway to check if an obj
dependency is also a src dependency.

Update dirdeps/meta bits from latest bmake.

Update meta* from bmake-20161212

Update meta2deps to fix crash when using -X with M2D_EXCLUDES.

Update to latest versions.

Latest version.
Report better parse errors.

Allow caller to pass a TARGET_SPEC which may be more complex than
just MACHINE, for recognizing objects which do not need qualifying
in dirdeps.

Sync latest versions

sync latest meta2deps

If self.machine is host we need to also trim self.host_target from
objroots to ensure we do not get confused.

Latest *dirdeps.mk and meta2deps

Latest dirdeps etc from Juniper Networks.

Sync FreeBSD's bmake branch with Juniper's internal bmake branch.

Requested by: Simon Gerraty <sjg@juniper.net>