Add support for AES working in Galois Counter Mode.
The following algorithms are added:
gcm(aes)
rfc4106(gcm(aes))
rfc4543(gcm(aes))

There is a limitation related to IV size, similar to the one present in
SW implementation (crypto/gcm.c):
The only IV size allowed is 12 bytes. It will be padded by HW to the right
with 0x0000_0001 (up to 16 bytes - AES block size), according to the
GCM specification.
Signed-off-by: Horia Geantă <horia.geanta@nxp.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>