[PATCH] Define BITS_PER_BYTE

This can make the intent behind some arithmetic expressions clearer.

Signed-off-by: Bryan O'Sullivan <bos@pathscale.com>
Signed-off-by: Adrian Bunk <bunk@stusta.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>