net: sunbmac: remove unnecessary dev_set_drvdata()

Unnecessary dev_set_drvdata() is removed, because the driver core
clears the driver data to NULL after device_release or on probe failure.
Signed-off-by: Libo Chen <libo.chen@huawei.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

drivers/net/ethernet/sun/sunbmac.c

@@ -1259,8 +1259,6 @@ static int bigmac_sbus_remove(struct platform_device *op)
 
 	free_netdev(net_dev);
 
-	dev_set_drvdata(&op->dev, NULL);
-
 	return 0;
 }