Bluetooth: Add BT_DBG to l2cap_sock_shutdown()

Add helpful BT_DBG debug to l2cap_sock_shutdown()
and __l2cap_wait_ack() so that the code flow can
be analysed.
Signed-off-by: NDean Jenkins <Dean_Jenkins@mentor.com>
Signed-off-by: NMarcel Holtmann <marcel@holtmann.org>

net/bluetooth/l2cap_sock.c

@@ -1063,6 +1063,8 @@ static int __l2cap_wait_ack(struct sock *sk, struct l2cap_chan *chan)
 	add_wait_queue(sk_sleep(sk), &wait);
 	set_current_state(TASK_INTERRUPTIBLE);
 	do {
+		BT_DBG("Waiting for %d ACKs", chan->unacked_frames);
+
 		if (!timeo)
 			timeo = HZ/5;
 
@@ -1146,6 +1148,8 @@ static int l2cap_sock_shutdown(struct socket *sock, int how)
 	l2cap_chan_put(chan);
 	sock_put(sk);
 
+	BT_DBG("err: %d", err);
+
 	return err;
 }