bitfield: add u8 helpers

There's no reason why we shouldn't pack/unpack bits into/from
u8 values/registers/etc., so add u8 helpers.

Use the ____MAKE_OP() macro directly to avoid having nonsense
le8_encode_bits() and similar functions.
Reviewed-by: NAndy Shevchenko <andy.shevchenko@gmail.com>
Signed-off-by: NJohannes Berg <johannes@sipsolutions.net>
Signed-off-by: NKalle Valo <kvalo@codeaurora.org>

include/linux/bitfield.h

@@ -143,6 +143,7 @@ static __always_inline base type##_get_bits(__##type v, base field)	\
 	____MAKE_OP(le##size,u##size,cpu_to_le##size,le##size##_to_cpu)	\
 	____MAKE_OP(be##size,u##size,cpu_to_be##size,be##size##_to_cpu)	\
 	____MAKE_OP(u##size,u##size,,)
+____MAKE_OP(u8,u8,,)
 __MAKE_OP(16)
 __MAKE_OP(32)
 __MAKE_OP(64)