net: mark net_proto_ops as const

All usages of structure net_proto_ops should be declared const.

Signed-off-by: Stephen Hemminger <shemminger@vyatta.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/net/x25/af_x25.c b/net/x25/af_x25.c
index 7fa9c7a..ebbfe6b 100644
--- a/net/x25/af_x25.c
+++ b/net/x25/af_x25.c
@@ -1476,7 +1476,7 @@
 	return rc;
 }
 
-static struct net_proto_family x25_family_ops = {
+static const struct net_proto_family x25_family_ops = {
 	.family =	AF_X25,
 	.create =	x25_create,
 	.owner	=	THIS_MODULE,