Add atomic_sub_and_test() to sparc32, implemented in terms of
atomic_sub_return(), so reiser4 can be simultaneously microoptimized for
x86 and made to pass compilation testing on sparc32.
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>