netdev: make net_device_ops const

More drivers where net_device_ops should be const.

Signed-off-by: Stephen Hemminger <shemminger@vyatta.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/drivers/net/ethernet/emulex/benet/be_main.c b/drivers/net/ethernet/emulex/benet/be_main.c
index 6c46753..a6bcdb5 100644
--- a/drivers/net/ethernet/emulex/benet/be_main.c
+++ b/drivers/net/ethernet/emulex/benet/be_main.c
@@ -3080,7 +3080,7 @@
 	return status;
 }
 
-static struct net_device_ops be_netdev_ops = {
+static const struct net_device_ops be_netdev_ops = {
 	.ndo_open		= be_open,
 	.ndo_stop		= be_close,
 	.ndo_start_xmit		= be_xmit,