net: convert remaining non-symbolic return values in ndo_start_xmit() functions

This patch converts the remaining occurences of raw return values to their
symbolic counterparts in ndo_start_xmit() functions that were missed by the
previous automatic conversion.

Additionally code that assumed the symbolic value of NETDEV_TX_OK to be zero
is changed to explicitly use NETDEV_TX_OK.

Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/drivers/s390/net/lcs.c b/drivers/s390/net/lcs.c
index 8c67590..a70de9b 100644
--- a/drivers/s390/net/lcs.c
+++ b/drivers/s390/net/lcs.c
@@ -1553,24 +1553,24 @@
 		 struct net_device *dev)
 {
 	struct lcs_header *header;
-	int rc = 0;
+	int rc = NETDEV_TX_OK;
 
 	LCS_DBF_TEXT(5, trace, "hardxmit");
 	if (skb == NULL) {
 		card->stats.tx_dropped++;
 		card->stats.tx_errors++;
-		return 0;
+		return NETDEV_TX_OK;
 	}
 	if (card->state != DEV_STATE_UP) {
 		dev_kfree_skb(skb);
 		card->stats.tx_dropped++;
 		card->stats.tx_errors++;
 		card->stats.tx_carrier_errors++;
-		return 0;
+		return NETDEV_TX_OK;
 	}
 	if (skb->protocol == htons(ETH_P_IPV6)) {
 		dev_kfree_skb(skb);
-		return 0;
+		return NETDEV_TX_OK;
 	}
 	netif_stop_queue(card->dev);
 	spin_lock(&card->lock);