and multiply functions from the old libkern. The m68010 versions
are only compiled when __mc68010__ is defined, presently that's
only done when building for sun2.
Reviewed by christos.
Some Makefiles for standalone programs already have it.
XXX Old src/sys/lib/libkern/arch/mips/memcpy.S had some #ifdef MIPS3_5900
XXX which added some extra nops, but this new common bcopy.S doesn't.