[PATCH] bitops: update include/asm-generic/bitops.h

Currently include/asm-generic/bitops.h is not referenced from anywhere.  But
it will be the benefit of those who are trying to port Linux to another
architecture.

So update it by same manner

Signed-off-by: Akinobu Mita <mita@miraclelinux.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>