net/sonic: Remove explicit memory barriers

The explicit memory barriers are redundant now that proper locking and
MMIO accessors have been employed.
Tested-by: NStan Johnson <userm57@yahoo.com>
Signed-off-by: NFinn Thain <fthain@telegraphics.com.au>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

drivers/net/ethernet/natsemi/sonic.c

@@ -311,12 +311,10 @@ static int sonic_send_packet(struct sk_buff *skb, struct net_device *dev)
 	sonic_tda_put(dev, entry, SONIC_TD_LINK,
 		sonic_tda_get(dev, entry, SONIC_TD_LINK) | SONIC_EOL);
 
-	wmb();
 	lp->tx_len[entry] = length;
 	lp->tx_laddr[entry] = laddr;
 	lp->tx_skb[entry] = skb;
 
-	wmb();
 	sonic_tda_put(dev, lp->eol_tx, SONIC_TD_LINK,
 				  sonic_tda_get(dev, lp->eol_tx, SONIC_TD_LINK) & ~SONIC_EOL);
 	lp->eol_tx = entry;