net: aquantia: fix aq_ndev_start_xmit()'s return type

The method ndo_start_xmit() is defined as returning an 'netdev_tx_t',
which is a typedef for an enum type, but the implementation in this
driver returns an 'int'.

Fix this by returning 'netdev_tx_t' in this driver too.
Signed-off-by: Luc Van Oostenryck <luc.vanoostenryck@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

drivers/net/ethernet/aquantia/atlantic/aq_main.c

@@ -95,7 +95,7 @@ static int aq_ndev_close(struct net_device *ndev)
 	return err;
 }
 
-static int aq_ndev_start_xmit(struct sk_buff *skb, struct net_device *ndev)
+static netdev_tx_t aq_ndev_start_xmit(struct sk_buff *skb, struct net_device *ndev)
 {
 	struct aq_nic_s *aq_nic = netdev_priv(ndev);