net: use NETDEV_TX_OK instead of 0 in ndo_start_xmit() functions

This patch is the result of an automatic spatch transformation to convert
all ndo_start_xmit() return values of 0 to NETDEV_TX_OK.

Some occurences are missed by the automatic conversion, those will be
handled in a seperate patch.

Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/net/bridge/br_device.c b/net/bridge/br_device.c
index 18538d7..15d43ba 100644
--- a/net/bridge/br_device.c
+++ b/net/bridge/br_device.c
@@ -39,7 +39,7 @@
 	else
 		br_flood_deliver(br, skb);
 
-	return 0;
+	return NETDEV_TX_OK;
 }
 
 static int br_dev_open(struct net_device *dev)