crypto: caam - fix asynchronous hash

ahash_alg->setkey is updated to ahash_nosetkey in ahash.c
so checking setkey() function to determine hmac algorithm is not valid.

to fix this added is_hmac variable in structure caam_hash_alg to determine
whether the algorithm is hmac or not.

Fixes: 2f1f34c1

 ("crypto: ahash - optimize performance when wrapping shash")
Signed-off-by: Gaurav Jain <gaurav.jain@nxp.com>
Reviewed-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>