integrity: remove redundant initialization of variable ret

The variable ret is being initialized with a value that is never read
and it is being updated later with a new value.  The initialization is
redundant and can be removed.

Fixes: eb5798f2 ("integrity: convert digsig to akcipher api")
Signed-off-by: Colin Ian King <colin.king@canonical.com>
Acked-by: James Morris <jamorris@linux.microsoft.com>
Addresses-Coverity: ("Unused value")
Signed-off-by: Mimi Zohar <zohar@linux.ibm.com>

security/integrity/digsig_asymmetric.c

@@ -79,7 +79,7 @@ int asymmetric_verify(struct key *keyring, const char *sig,
 	struct public_key_signature pks;
 	struct signature_v2_hdr *hdr = (struct signature_v2_hdr *)sig;
 	struct key *key;
-	int ret = -ENOMEM;
+	int ret;
 
 	if (siglen <= sizeof(*hdr))
 		return -EBADMSG;