net: broadcom: replace dev_kfree_skb_irq by dev_consume_skb_irq for drop profiles

dev_consume_skb_irq() should be called in sbdma_tx_process() 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/ethernet/broadcom/sb1250-mac.c

@@ -1288,7 +1288,7 @@ static void sbdma_tx_process(struct sbmac_softc *sc, struct sbmacdma *d,
 		 * for transmits, we just free buffers.
 		 */
 
-		dev_kfree_skb_irq(sb);
+		dev_consume_skb_irq(sb);
 
 		/*
 		 * .. and advance to the next buffer.