target: Release se_cmd when LUN lookup fails for TMR

When transport_lookup_tmr_lun() fails and we return a task management
response from target_complete_tmr_failure(), we need to call
transport_cmd_check_stop_to_fabric() to release the last ref to the
cmd after calling se_tfo->queue_tm_rsp(), or else we will never remove
the failed TMR from the session command list (and we'll end up waiting
forever when trying to tear down the session).

(nab: Fix minor compile breakage)

Signed-off-by: Roland Dreier <roland@purestorage.com>
Cc: stable@vger.kernel.org
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>

drivers/target/target_core_transport.c

@@ -1393,6 +1393,8 @@ static void target_complete_tmr_failure(struct work_struct *work)
 
 	se_cmd->se_tmr_req->response = TMR_LUN_DOES_NOT_EXIST;
 	se_cmd->se_tfo->queue_tm_rsp(se_cmd);
+
+	transport_cmd_check_stop_to_fabric(se_cmd);
 }
 
 /**