drivers/net: const-ify ethtool_ops declarations

Signed-off-by: Jeff Garzik <jeff@garzik.org>
diff --git a/drivers/net/qla3xxx.c b/drivers/net/qla3xxx.c
index c729aee..09a481a 100644
--- a/drivers/net/qla3xxx.c
+++ b/drivers/net/qla3xxx.c
@@ -1588,7 +1588,7 @@
 	qdev->msg_enable = value;
 }
 
-static struct ethtool_ops ql3xxx_ethtool_ops = {
+static const struct ethtool_ops ql3xxx_ethtool_ops = {
 	.get_settings = ql_get_settings,
 	.get_drvinfo = ql_get_drvinfo,
 	.get_perm_addr = ethtool_op_get_perm_addr,