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>
diff --git a/drivers/net/hp100.c b/drivers/net/hp100.c
index d1b6338..a9a1a99 100644
--- a/drivers/net/hp100.c
+++ b/drivers/net/hp100.c
@@ -240,9 +240,10 @@
 
 static int hp100_open(struct net_device *dev);
 static int hp100_close(struct net_device *dev);
-static int hp100_start_xmit(struct sk_buff *skb, struct net_device *dev);
-static int hp100_start_xmit_bm(struct sk_buff *skb,
-			       struct net_device *dev);
+static netdev_tx_t hp100_start_xmit(struct sk_buff *skb,
+				    struct net_device *dev);
+static netdev_tx_t hp100_start_xmit_bm(struct sk_buff *skb,
+				       struct net_device *dev);
 static void hp100_rx(struct net_device *dev);
 static struct net_device_stats *hp100_get_stats(struct net_device *dev);
 static void hp100_misc_interrupt(struct net_device *dev);
@@ -1483,7 +1484,8 @@
  */
 
 /* tx function for busmaster mode */
-static int hp100_start_xmit_bm(struct sk_buff *skb, struct net_device *dev)
+static netdev_tx_t hp100_start_xmit_bm(struct sk_buff *skb,
+				       struct net_device *dev)
 {
 	unsigned long flags;
 	int i, ok_flag;
@@ -1635,7 +1637,8 @@
 }
 
 /* tx function for slave modes */
-static int hp100_start_xmit(struct sk_buff *skb, struct net_device *dev)
+static netdev_tx_t hp100_start_xmit(struct sk_buff *skb,
+				    struct net_device *dev)
 {
 	unsigned long flags;
 	int i, ok_flag;