net: trans_start cleanups

Now that core network takes care of trans_start updates, dont do it
in drivers themselves, if possible. Drivers can avoid one cache miss
(on dev->trans_start) in their start_xmit() handler.

Exceptions are NETIF_F_LLTX drivers

Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/drivers/net/3c509.c b/drivers/net/3c509.c
index ab9bb3c..54deaa9 100644
--- a/drivers/net/3c509.c
+++ b/drivers/net/3c509.c
@@ -807,7 +807,7 @@
 		   dev->name, inb(ioaddr + TX_STATUS), inw(ioaddr + EL3_STATUS),
 		   inw(ioaddr + TX_FREE));
 	dev->stats.tx_errors++;
-	dev->trans_start = jiffies;
+	dev->trans_start = jiffies; /* prevent tx timeout */
 	/* Issue TX_RESET and TX_START commands. */
 	outw(TxReset, ioaddr + EL3_CMD);
 	outw(TxEnable, ioaddr + EL3_CMD);
@@ -868,7 +868,6 @@
 	/* ... and the packet rounded to a doubleword. */
 	outsl(ioaddr + TX_FIFO, skb->data, (skb->len + 3) >> 2);
 
-	dev->trans_start = jiffies;
 	if (inw(ioaddr + TX_FREE) > 1536)
 		netif_start_queue(dev);
 	else