ethernet: Delete unnecessary checks before the macro call “dev_kfree_skb”

The dev_kfree_skb() function performs also input parameter validation.
Thus the test around the shown calls is not needed.

This issue was detected by using the Coccinelle software.

Signed-off-by: Markus Elfring <elfring@users.sourceforge.net>
Signed-off-by: David S. Miller <davem@davemloft.net>

drivers/net/ethernet/sgi/meth.c

@@ -247,8 +247,7 @@ static void meth_free_tx_ring(struct meth_private *priv)
 
 	/* Remove any pending skb */
 	for (i = 0; i < TX_RING_ENTRIES; i++) {
-		if (priv->tx_skbs[i])
-			dev_kfree_skb(priv->tx_skbs[i]);
+		dev_kfree_skb(priv->tx_skbs[i]);
 		priv->tx_skbs[i] = NULL;
 	}
 	dma_free_coherent(&priv->pdev->dev, TX_RING_BUFFER_SIZE, priv->tx_ring,