[NET]: Transform skb_queue_len() binary tests into skb_queue_empty()

This is part of the grand scheme to eliminate the qlen
member of skb_queue_head, and subsequently remove the
'list' member of sk_buff.

Most users of skb_queue_len() want to know if the queue is
empty or not, and that's trivially done with skb_queue_empty()
which doesn't use the skb_queue_head->qlen member and instead
uses the queue list emptyness as the test.

Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/net/irda/irlap_frame.c b/net/irda/irlap_frame.c
index 040abe7..6dafbb4 100644
--- a/net/irda/irlap_frame.c
+++ b/net/irda/irlap_frame.c
@@ -1018,11 +1018,10 @@
 	/*
 	 *  We can now fill the window with additional data frames
 	 */
-	while (skb_queue_len( &self->txq) > 0) {
+	while (!skb_queue_empty(&self->txq)) {
 
 		IRDA_DEBUG(0, "%s(), sending additional frames!\n", __FUNCTION__);
-		if ((skb_queue_len( &self->txq) > 0) &&
-		    (self->window > 0)) {
+		if (self->window > 0) {
 			skb = skb_dequeue( &self->txq);
 			IRDA_ASSERT(skb != NULL, return;);
 
@@ -1031,8 +1030,7 @@
 			 *  bit cleared
 			 */
 			if ((self->window > 1) &&
-			    skb_queue_len(&self->txq) > 0)
-			{
+			    !skb_queue_empty(&self->txq)) {
 				irlap_send_data_primary(self, skb);
 			} else {
 				irlap_send_data_primary_poll(self, skb);