[PATCH] slob: introduce mm/util.c for shared functions

Add mm/util.c for functions common between SLAB and SLOB.

Signed-off-by: Matt Mackall <mpm@selenic.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>