netdev: convert bulk of drivers to netdev_tx_t

In a couple of cases collapse some extra code like:
   int retval = NETDEV_TX_OK;
   ...
   return retval;
into
   return NETDEV_TX_OK;

Signed-off-by: Stephen Hemminger <shemminger@vyatta.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

drivers/net/atlx/atl1.c

@@ -2349,7 +2349,8 @@ static void atl1_tx_queue(struct atl1_adapter *adapter, u16 count,
 	atomic_set(&tpd_ring->next_to_use, next_to_use);
 }
 
-static int atl1_xmit_frame(struct sk_buff *skb, struct net_device *netdev)
+static netdev_tx_t atl1_xmit_frame(struct sk_buff *skb,
+					 struct net_device *netdev)
 {
 	struct atl1_adapter *adapter = netdev_priv(netdev);
 	struct atl1_tpd_ring *tpd_ring = &adapter->tpd_ring;

drivers/net/atlx/atl2.c

@@ -821,7 +821,8 @@ static inline int TxdFreeBytes(struct atl2_adapter *adapter)
 		(int) (txd_read_ptr - adapter->txd_write_ptr - 1);
 }
 
-static int atl2_xmit_frame(struct sk_buff *skb, struct net_device *netdev)
+static netdev_tx_t atl2_xmit_frame(struct sk_buff *skb,
+					 struct net_device *netdev)
 {
 	struct atl2_adapter *adapter = netdev_priv(netdev);
 	struct tx_pkt_header *txph;