net: wan: wanxl: replace dev_kfree_skb_irq by dev_consume_skb_irq for drop profiles

dev_consume_skb_irq() should be called in wanxl_tx_intr() when skb
xmit done. It makes drop profiles(dropwatch, perf) more friendly.
Signed-off-by: NYang Wei <yang.wei9@zte.com.cn>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

drivers/net/wan/wanxl.c

@@ -185,7 +185,7 @@ static inline void wanxl_tx_intr(struct port *port)
                 desc->stat = PACKET_EMPTY; /* Free descriptor */
 		pci_unmap_single(port->card->pdev, desc->address, skb->len,
 				 PCI_DMA_TODEVICE);
-		dev_kfree_skb_irq(skb);
+		dev_consume_skb_irq(skb);
                 port->tx_in = (port->tx_in + 1) % TX_BUFFERS;
         }
 }