cifs: rename a variable in SendReceive()

Smatch gets confused because we sometimes refer to "server->srv_mutex" and
sometimes to "sess->server->srv_mutex".  They refer to the same lock so
let's just make this consistent.
Signed-off-by: NDan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: NSteve French <stfrench@microsoft.com>

fs/cifs/transport.c

@@ -1287,7 +1287,7 @@ SendReceive(const unsigned int xid, struct cifs_ses *ses,
 
 	rc = allocate_mid(ses, in_buf, &midQ);
 	if (rc) {
-		mutex_unlock(&ses->server->srv_mutex);
+		mutex_unlock(&server->srv_mutex);
 		/* Update # of requests on wire to server */
 		add_credits(server, &credits, 0);
 		return rc;