virtio_net: Call dev_kfree_skb_any instead of dev_kfree_skb.

Replace dev_kfree_skb with dev_kfree_skb_any in start_xmit which can
be called in hard irq and other contexts.

start_xmit only frees skbs that it is dropping.
Signed-off-by: N"Eric W. Biederman" <ebiederm@xmission.com>

drivers/net/virtio_net.c

@@ -883,7 +883,7 @@ static netdev_tx_t start_xmit(struct sk_buff *skb, struct net_device *dev)
 			dev_warn(&dev->dev,
 				 "Unexpected TXQ (%d) queue failure: %d\n", qnum, err);
 		dev->stats.tx_dropped++;
-		kfree_skb(skb);
+		dev_kfree_skb_any(skb);
 		return NETDEV_TX_OK;
 	}