chcr_ktls: use AES library for single use cipher

Allocating a cipher via the crypto API only to free it again after using
it to encrypt a single block is unnecessary in cases where the algorithm
is known at compile time. So replace this pattern with a call to the AES
library.

Cc: Ayush Sawal <ayush.sawal@chelsio.com>
Cc: Vinay Kumar Yadav <vinay.yadav@chelsio.com>
Cc: Rohit Maheshwari <rohitm@chelsio.com>
Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
Reviewed-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>