net: lantiq_etop: don't free skb when returning NETDEV_TX_BUSY

The ndo_start_xmit() method must not free skb when returning
NETDEV_TX_BUSY, since caller is going to requeue freed skb.

Fixes: 504d4721ee ("MIPS: Lantiq: Add ethernet driver")
Signed-off-by: Zhang Changzhong <zhangchangzhong@huawei.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

drivers/net/ethernet/lantiq_etop.c

@@ -485,7 +485,6 @@ ltq_etop_tx(struct sk_buff *skb, struct net_device *dev)
 	len = skb->len < ETH_ZLEN ? ETH_ZLEN : skb->len;
 
 	if ((desc->ctl & (LTQ_DMA_OWN | LTQ_DMA_C)) || ch->skb[ch->dma.desc]) {
-		dev_kfree_skb_any(skb);
 		netdev_err(dev, "tx ring full\n");
 		netif_tx_stop_queue(txq);
 		return NETDEV_TX_BUSY;