drivers/net: const-ify ethtool_ops declarations

Signed-off-by: Jeff Garzik <jeff@garzik.org>
diff --git a/drivers/net/amd8111e.c b/drivers/net/amd8111e.c
index a77df85..28855a0 100644
--- a/drivers/net/amd8111e.c
+++ b/drivers/net/amd8111e.c
@@ -1645,7 +1645,7 @@
 	return 0;
 }
 
-static struct ethtool_ops ops = {
+static const struct ethtool_ops ops = {
 	.get_drvinfo = amd8111e_get_drvinfo,
 	.get_regs_len = amd8111e_get_regs_len,
 	.get_regs = amd8111e_get_regs,