net: make ethtool_ops const

Auditing all usage of ethtool_ops found several drivers that
are not declaring the struct const when it should be.

Signed-off-by: Stephen Hemminger <shemminger@vyatta.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/drivers/net/ethernet/renesas/sh_eth.c b/drivers/net/ethernet/renesas/sh_eth.c
index ebfb682..fc9bda9 100644
--- a/drivers/net/ethernet/renesas/sh_eth.c
+++ b/drivers/net/ethernet/renesas/sh_eth.c
@@ -1369,13 +1369,13 @@
 	}
 }
 
-static struct ethtool_ops sh_eth_ethtool_ops = {
+static const struct ethtool_ops sh_eth_ethtool_ops = {
 	.get_settings	= sh_eth_get_settings,
 	.set_settings	= sh_eth_set_settings,
-	.nway_reset		= sh_eth_nway_reset,
+	.nway_reset	= sh_eth_nway_reset,
 	.get_msglevel	= sh_eth_get_msglevel,
 	.set_msglevel	= sh_eth_set_msglevel,
-	.get_link		= ethtool_op_get_link,
+	.get_link	= ethtool_op_get_link,
 	.get_strings	= sh_eth_get_strings,
 	.get_ethtool_stats  = sh_eth_get_ethtool_stats,
 	.get_sset_count     = sh_eth_get_sset_count,