openvswitch: introduce rtnl ops stub

This stub now allows userspace to see IFLA_INFO_KIND for ovs master and
IFLA_INFO_SLAVE_KIND for slave.

Signed-off-by: Jiri Pirko <jiri@resnulli.us>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/net/openvswitch/vport-internal_dev.h b/net/openvswitch/vport-internal_dev.h
index 9a7d30e..1b179a1 100644
--- a/net/openvswitch/vport-internal_dev.h
+++ b/net/openvswitch/vport-internal_dev.h
@@ -24,5 +24,7 @@
 
 int ovs_is_internal_dev(const struct net_device *);
 struct vport *ovs_internal_dev_get_vport(struct net_device *);
+int ovs_internal_dev_rtnl_link_register(void);
+void ovs_internal_dev_rtnl_link_unregister(void);
 
 #endif /* vport-internal_dev.h */