[PATCH] x86_64: Some cleanup in setup64.c

Minor cleanup.

Move things into their include files, remove obsolete includes, fix
indentation, remove obsolete special cases etc.

I also added the per cpu section to asm-generic/sections.h and fixed
init/main.c to use it.

Signed-off-by: Andi Kleen <ak@suse.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>