crypto: camellia - simplify key setup and CAMELLIA_ROUNDSM macro

camellia_setup_tail() applies 'inverse of the last half of P-function' to
subkeys, which is unneeded if keys are applied directly to yl/yr in
CAMELLIA_ROUNDSM.

Patch speeds up key setup and should speed up CAMELLIA_ROUNDSM as applying
key to yl/yr early has less register dependencies.

Quick tcrypt camellia results:
 x86_64, AMD Phenom II, ~5% faster
 x86_64, Intel Core 2, ~0.5% faster
 i386, Intel Atom N270, ~1% faster

Signed-off-by: Jussi Kivilinna <jussi.kivilinna@mbnet.fi>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>