* split PRU_SENSE functionality out of mpls_usrreq() and place into
  separate mpls_stat(struct socket *, struct stat *) function

missed this in previous commit, fixes build of ALL kernel.
Minor updates - I've attempted to catch the most glaringly outdated
statements but haven't made any effort yet to rewrite the main content.
Reduce diffs to prepare to merge these files.
New sentence, new line.
Merge and share boot.c between normal boot and netboot by dumb #ifdefs.

Tested on XM6i.
Don't install EXTRAHTMLFILES if MKHTML is "no".
Check .evs_used==0 instead of .evs_cmds==NULL. evs_cmds would not be NULL if
another _makecmds() had allocated and deallocated VMCMDs (not the case
currently).
make sure struct bat is aligned to 8 bytes as we shift them 3 bits.

fixes PReP lossage as reported on port-powerpc and port-prep.
thanks to makoto@ki.nu and kiyohara@netbsd.
Probe the actual memory size and warn if it's different from SRAM value.

Without this, ancient X680x0 machines with a dead SRAM battery will
fail to boot silently (or hang right after early copyright messages).

Discussed with and reviewed by isaki@.

XXX: probably we should rather pass the probed memory size to a kernel
XXX: than the size value stored in SRAM..
fix docs for MKHTML=no
mention requirements for custom kernels.
fix pasto in function name should be natm_stat instead of natm_ioctl
Use a macro instead of always putting __func__ and __LINE__.
Remove this (symtabindex == -1) check; it is already handled by (nsym != 1).
Put a KASSERT instead.
Register a null power handler if acpiec fails to attach.

On one of my machines, there's no _GPE method, so
acpiec_parse_gpe_package fails, and the only function acpiec(4)
serves is to inhibit suspend/resume.

XXX We should really put the power handlers in the cfattach so that
it's not necessary to register a null power handler in every error
branch of every device's attach routine...
Modify Linux timer API to add teardown_timer.

del_timer_sync does not actually destroy the timer so it can't be
reused again -- but Linux has no routine to do that.  So we'll have
to add that in where appropriate.
* #include <sys/kmem.h> for kmem_intr_xxx()
* ansify pcb_add() function signature and make its prototype parameter
  types match its definition.
Call teardown_timer in drm_vblank_cleanup.
Call teardown_timer in i915_driver_unload.
* #include <sys/kmem.h> for kmem_intr_free()
* add missing variables used by natm_attach(), natm_ioctl()