Encouraging the compiler to inline xts_tweak_encdec increases the
performance for xts-aes-128 when built with gcrypt:
Encrypt: 545 MB/s -> 580 MB/s
Decrypt: 568 MB/s -> 602 MB/s
Reviewed-by: Alberto Garcia <berto@igalia.com>
Signed-off-by: Daniel P. Berrangé <berrange@redhat.com>