crypto: chcr - Use cipher instead of Block Cipher in gcm setkey

1 Block of encrption can be done with aes-generic. no need of
cbc(aes). This patch replaces cbc(aes-generic) with aes-generic.

Signed-off-by: Harsh Jain <harsh@chelsio.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>