sun4i-emac: Call dev_consume_skb_any instead of dev_kfree_skb.

Replace dev_kfree_skb with dev_consume_skb_any in emacs_start_xmit
which can be called in hard irq and other contexts.

emac_start_xmit always transmits the packet making dev_consume_skb
the appropriate function to call.
Signed-off-by: N"Eric W. Biederman" <ebiederm@xmission.com>

drivers/net/ethernet/allwinner/sun4i-emac.c

@@ -476,7 +476,7 @@ static int emac_start_xmit(struct sk_buff *skb, struct net_device *dev)
 	spin_unlock_irqrestore(&db->lock, flags);
 
 	/* free this SKB */
-	dev_kfree_skb(skb);
+	dev_consume_skb_any(skb);
 
 	return NETDEV_TX_OK;
 }