crypto: s390/sha - replace raw value by their coresponding define

SHA_MAX_STATE_SIZE is just the number of u32 word for SHA512.
So replace the raw value "16" by their meaning (SHA512_DIGEST_SIZE / 4)
Signed-off-by: NLABBE Corentin <clabbe.montjoie@gmail.com>
Signed-off-by: NHerbert Xu <herbert@gondor.apana.org.au>

arch/s390/crypto/sha.h

@@ -19,7 +19,7 @@
 #include <crypto/sha.h>
 
 /* must be big enough for the largest SHA variant */
-#define SHA_MAX_STATE_SIZE	16
+#define SHA_MAX_STATE_SIZE	(SHA512_DIGEST_SIZE / 4)
 #define SHA_MAX_BLOCK_SIZE      SHA512_BLOCK_SIZE
 
 struct s390_sha_ctx {