crypto: camellia - Use kernel-provided bitops, unaligned access helpers

Remove the private implementation of 32-bit rotation and unaligned
access with byteswapping.

As a bonus, fixes sparse warnings:
crypto/camellia.c:602:2: warning: cast to restricted __be32
crypto/camellia.c:603:2: warning: cast to restricted __be32
crypto/camellia.c:604:2: warning: cast to restricted __be32
crypto/camellia.c:605:2: warning: cast to restricted __be32
crypto/camellia.c:710:2: warning: cast to restricted __be32
crypto/camellia.c:711:2: warning: cast to restricted __be32
crypto/camellia.c:712:2: warning: cast to restricted __be32
crypto/camellia.c:713:2: warning: cast to restricted __be32
crypto/camellia.c:714:2: warning: cast to restricted __be32
crypto/camellia.c:715:2: warning: cast to restricted __be32
crypto/camellia.c:716:2: warning: cast to restricted __be32
crypto/camellia.c:717:2: warning: cast to restricted __be32

Signed-off-by: Harvey Harrison <harvey.harrison@gmail.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>