Merging few files from i386/amd64 into x86

[Mindaugas Rasiukevicius <rmind%netbsd.org@localhost>]

Hello,

I would like to merge couple files from i386 and amd64 into x86, since they
basically duplicate the functionality:

sys/arch/{i386|amd64}/vm_machdep.c
sys/arch/{i386|amd64}/ipifuncs.c
sys/arch/{i386|amd64}/mem.c

The ipifuncs.c would be merged with existing x86/ipi.c file. Other potential
candidates for merge would be trap.c and syscall.c files. Few #ifdefs and
macros would help to keep i386 and amd64 in sync.

Any objections?

P.S. Please keep me in CC, I am not in the lists (yet).

-- 
Best regards,
Mindaugas