tcm_fc: Fix possible lock to unlock type deadlock

There is a typo here, it should be an unlock instead of a lock.  The
original code will deadlock.
Signed-off-by: Dan Carpenter <error27@gmail.com>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>

drivers/target/tcm_fc/tfc_sess.c

@@ -332,7 +332,7 @@ void ft_sess_close(struct se_session *se_sess)
 	lport = sess->tport->lport;
 	port_id = sess->port_id;
 	if (port_id == -1) {
-		mutex_lock(&ft_lport_lock);
+		mutex_unlock(&ft_lport_lock);
 		return;
 	}
 	FT_SESS_DBG("port_id %x\n", port_id);