net: use skb_queue_empty_lockless() in poll() handlers

Many poll() handlers are lockless. Using skb_queue_empty_lockless()
instead of skb_queue_empty() is more appropriate.

Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

net/decnet/af_decnet.c

@@ -1205,7 +1205,7 @@ static __poll_t dn_poll(struct file *file, struct socket *sock, poll_table  *wai
 	struct dn_scp *scp = DN_SK(sk);
 	__poll_t mask = datagram_poll(file, sock, wait);
 
-	if (!skb_queue_empty(&scp->other_receive_queue))
+	if (!skb_queue_empty_lockless(&scp->other_receive_queue))
 		mask |= EPOLLRDBAND;
 
 	return mask;