[NET]: Hide the queue_mapping field inside netif_subqueue_stopped

Many places get the queue_mapping field from skb to pass it to the
netif_subqueue_stopped() which will be 0 in any case.

Make the helper that works with sk_buff

Signed-off-by: Pavel Emelyanov <xemul@openvz.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/net/core/netpoll.c b/net/core/netpoll.c
index 95daba6..bf8d18f 100644
--- a/net/core/netpoll.c
+++ b/net/core/netpoll.c
@@ -67,7 +67,7 @@
 		local_irq_save(flags);
 		netif_tx_lock(dev);
 		if ((netif_queue_stopped(dev) ||
-		     netif_subqueue_stopped(dev, skb->queue_mapping)) ||
+		     netif_subqueue_stopped(dev, skb)) ||
 		     dev->hard_start_xmit(skb, dev) != NETDEV_TX_OK) {
 			skb_queue_head(&npinfo->txq, skb);
 			netif_tx_unlock(dev);
@@ -269,7 +269,7 @@
 		     tries > 0; --tries) {
 			if (netif_tx_trylock(dev)) {
 				if (!netif_queue_stopped(dev) &&
-				    !netif_subqueue_stopped(dev, skb->queue_mapping))
+				    !netif_subqueue_stopped(dev, skb))
 					status = dev->hard_start_xmit(skb, dev);
 				netif_tx_unlock(dev);