scsi: target: iscsi: calling iscsit_stop_session() inside iscsit_close_session() has no effect

iscsit_close_session() can only be called when nconn is zero (otherwise a
kernel panic is triggered). If nconn is zero then iscsit_stop_session()
does nothing and exits, so calling it makes no sense.

We still need to call iscsit_check_session_usage_count() because this
function will sleep if the session's refcount is not zero and we don't want
to destroy the session structure if it's still being referenced.

Link: https://lore.kernel.org/r/20200313170656.9716-4-mlombard@redhat.com
Tested-by: Rahul Kundu <rahul.kundu@chelsio.com>
Signed-off-by: Maurizio Lombardi <mlombard@redhat.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>

drivers/target/iscsi/iscsi_target.c

@@ -4381,8 +4381,7 @@ int iscsit_close_session(struct iscsi_session *sess)
 	 * restart the timer and exit.
 	 */
 	if (!in_interrupt()) {
-		if (iscsit_check_session_usage_count(sess) == 1)
-			iscsit_stop_session(sess, 1, 1);
+		iscsit_check_session_usage_count(sess);
 	} else {
 		if (iscsit_check_session_usage_count(sess) == 2) {
 			atomic_set(&sess->session_logout, 0);