Copy stable/9 to releng/9.3 as part of the 9.3-RELEASE cycle.

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

Copy head to stable/9 as part of 9.0-RELEASE release cycle.

Approved by: re (implicit)

Add macros for alternate entry points.

Remove advertising clause from University of California Regent's
license, per letter dated July 22, 1999 and email from Peter Wemm,
Alan Cox and Robert Watson.

Approved by: core, peter, alc, rwatson

- Fix placement of cvs ids in previous commit to match .S files in libc.
- gcc uses 32 byte alignment for functions regardless of profiling, so
follow suit.

I was wrong, the ENTRY bits in asm.h did have a purpose -- for userland.
Restore the bits and remove them from asmacros.h. *.S will now be asm.h
consumers.

Approved by: jake

The ENTRY bits were in two places. Remove the one not used (asm.h), but
presurve the nice comment by adding it to asmacros.h.

ASM versions of __FBSDID.

Define __ASM__ so that libc will know not to define C things.

Add kernel headers needed to build libc. Some are bogus and/or just enough
to compile.

Mostly obtained from: netbsd