net: wiznet: fix return type of ndo_start_xmit function

The method ndo_start_xmit() is defined as returning an 'netdev_tx_t',
which is a typedef for an enum type, so make sure the implementation in
this driver has returns 'netdev_tx_t' value, and change the function
return type to netdev_tx_t.

Found by coccinelle.
Signed-off-by: NYueHaibing <yuehaibing@huawei.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

drivers/net/ethernet/wiznet/w5100.c

@@ -835,7 +835,7 @@ static void w5100_tx_work(struct work_struct *work)
 	w5100_tx_skb(priv->ndev, skb);
 }
 
-static int w5100_start_tx(struct sk_buff *skb, struct net_device *ndev)
+static netdev_tx_t w5100_start_tx(struct sk_buff *skb, struct net_device *ndev)
 {
 	struct w5100_priv *priv = netdev_priv(ndev);
 

drivers/net/ethernet/wiznet/w5300.c

@@ -365,7 +365,7 @@ static void w5300_tx_timeout(struct net_device *ndev)
 	netif_wake_queue(ndev);
 }
 
-static int w5300_start_tx(struct sk_buff *skb, struct net_device *ndev)
+static netdev_tx_t w5300_start_tx(struct sk_buff *skb, struct net_device *ndev)
 {
 	struct w5300_priv *priv = netdev_priv(ndev);