drivers/net: const-ify ethtool_ops declarations

Signed-off-by: Jeff Garzik <jeff@garzik.org>
diff --git a/drivers/net/tulip/winbond-840.c b/drivers/net/tulip/winbond-840.c
index 264723b..2fca1ee 100644
--- a/drivers/net/tulip/winbond-840.c
+++ b/drivers/net/tulip/winbond-840.c
@@ -339,7 +339,7 @@
 static void set_rx_mode(struct net_device *dev);
 static struct net_device_stats *get_stats(struct net_device *dev);
 static int netdev_ioctl(struct net_device *dev, struct ifreq *rq, int cmd);
-static struct ethtool_ops netdev_ethtool_ops;
+static const struct ethtool_ops netdev_ethtool_ops;
 static int  netdev_close(struct net_device *dev);
 
 
@@ -1447,7 +1447,7 @@
 	debug = value;
 }
 
-static struct ethtool_ops netdev_ethtool_ops = {
+static const struct ethtool_ops netdev_ethtool_ops = {
 	.get_drvinfo		= netdev_get_drvinfo,
 	.get_settings		= netdev_get_settings,
 	.set_settings		= netdev_set_settings,