integrity: do zero padding of the key id

Latest KEYS code return error if hexadecimal string length id odd.
Fix it.
Signed-off-by: NDmitry Kasatkin <d.kasatkin@samsung.com>
Signed-off-by: NDavid Howells <dhowells@redhat.com>

security/integrity/digsig_asymmetric.c

@@ -28,7 +28,7 @@ static struct key *request_asymmetric_key(struct key *keyring, uint32_t keyid)
 	struct key *key;
 	char name[12];
 
-	sprintf(name, "id:%x", keyid);
+	sprintf(name, "id:%08x", keyid);
 
 	pr_debug("key search: \"%s\"\n", name);