Add m68k assembler version of __muldi3().

This is intended for 68060:
- GCC does not emit __muldi3() for 68020-40, that have 32 * 32 --> 64 mulul
- mulsl (and moveml), used in this code, are not implemented for 68010

In comparison with that from compiler_rt, this version saves:
- 12% of processing time
- 12 bytes of stack
- 50 bytes of code size
Also, slightly faster, memory saving, and smaller than libgcc version.

By examining with evcnt(9), __muldi3() is invoked more than 1000 times per
sec by kernel, which should justify to introduce assembler version of this
function.

Revert untested and unnecessary change in previous rev 1.36.

Our autobuild doesn't always reflect the latest fixes.

add mulsi3, needed by inet_addr.o

branches: 1.35.2;
Revert 1.33 and 1.34 for now, until either .INVISIBLE is reinstanciated
or random.S dropped.

Make random.S invisible for coldfire too (e.g. anything not "m68k")

use .INVISIBLE to hide random.S, instead of extra rules.

Merge riastradh-drm2 to HEAD.

Reorder a little to make clearer.

branches: 1.30.12; 1.30.22; 1.30.26; 1.30.34;
Move that majority of the 'SRCS+= foo.c' into the main Makefile.libkern.
Any .S files added by the arch/*/Makefile.inc cause the .c file to
be excluded.
Specific exclusions added using NO_SRCS to match previous files.
At least sparc, sparc64, i386, amd64 and vax GENERIC still build.
(There is a fubar with the naming of the byte-swap files ...)

Remove some .c files accidentally left on the .S lines

Split the lines that add .c to SRCS from those that add .S
No changes (apart from the order) intended.

- remove bcmp(9), bcopy(9), and bzero(9) from libkern since <sys/systm.h> has
macro which replace them with mem*() functions in #ifdef _KERNEL as noted
in man pages
- move declarations of bcopy(3) and bzero(3) into <lib/libsa/stand.h>
since they are still in libsa for some MD standalone sources
(I guess all bcmp(3) in standalone sources have been replaced with memcmp(3)
but they should be replaced with memcmp() anyway)

branches: 1.26.74; 1.26.84; 1.26.90;
merge ktrace-lwp.

Don't try to build random.S on 68010.

branches: 1.24.6;
add strtoul.c, it's now used in MI code.

Added brand-new integer multiply and divide support, used only
on the m68000.

On the m68000, if and only if gcc doesn't seem to know
where libgcc.a is, fall back to one under DESTDIR.

branches: 1.21.2;
When MACHINE_ARCH is m68000, compile ffs.c and random.c
instead of ffs.s and random.s, and sneak the libgcc
integer support routines into the list of library objects.

branches: 1.20.2;
Add a strcasecmp(), modified from chopps's strncasecmp().

branches: 1.19.12;
add memcmp.S memmove.S

Use the new .S files.

Sync with libc, and add random.S.

add rules like those in libc to build strchr() and strrchr() (the latter
is being added to libkern by this commit). remove strchr.c from
archs' Makefile.inc files to go along with this. (If an arch has
a .S version, it should be copied down and added to the apropriate
Makefile.inc.)

add memchr() to libkern

Implement assembly byte-swap functions.

Add byte-swapping functions (bswap16, bswap32, bswap64) to libkern.
Only assembly version for i386 bswap16 and bswap32 for now (bswap64 uses
bswap32). Contribution of assembly versions of these are welcome.
Add byte-swapping of ext2fs metadata for big-endian systems.
Tested on i386 and sparc.

branches: 1.12.8;
add strchr() to libkern. strchr.c copied from libc's "index.c", but with
appropriate definitions so that it'll build strchr(), and so that it builds
correctly in libkern (needed to #define NULL).

We use C flavors of the quad support functions in libkern.

Sync with libc

Add machine-independent assertion-checking support. macros are:

assert() which always does assertion checking
unless "NDEBUG" is defined.

KASSERT() which does assertion checking if DIAGNOSTIC
is defined.

KDASSERT() which does assertion checking if DEBUG is
define. This macro exists for compatibility
with existing ports' assertion checking macros.
(Assertion checking is not typically an
"expensive" operation, and DIAGNOSTIC should be
used for inexpensive consistency checks.)

locc() is unused. Remove it from the machine-independent kernel interface.

use assembly version of strcat (copied down from libc)

Add strncasecmp.c; extracted from ADOSFS adlookup.c.

new RCS ID format.

use .S

branches: 1.3.2;
change to use MACHINE_ARCH and update from libc

Move the SRCS from hp300 over to here, changing ffs.c to ffs.s.
Am I missing something obvious in doing this? This makes the
${ARCH}/Makefile.inc for 68k able to just set ARCH=m68k.

move 'boot' and 'libkern' into 'lib'. generally clean up 'kernel library'
building and dependencies.