ethoc: enable transmit time stamping.

This patch enables software (and phy device) transmit time stamping
for the OpenCores 10/100 MAC driver. Compile tested only.

Cc: Thierry Reding <thierry.reding@avionic-design.de>
Signed-off-by: Richard Cochran <richard.cochran@omicron.at>
Signed-off-by: David S. Miller <davem@conan.davemloft.net>

drivers/net/ethoc.c

@@ -875,6 +875,7 @@ static netdev_tx_t ethoc_start_xmit(struct sk_buff *skb, struct net_device *dev)
 	}
 
 	spin_unlock_irq(&priv->lock);
+	skb_tx_timestamp(skb);
 out:
 	dev_kfree_skb(skb);
 	return NETDEV_TX_OK;