dev: update __dev_notify_flags() to send rtnl msg

This patch only prepares the next one, there is no functional change.
Now, __dev_notify_flags() can also be used to notify flags changes via
rtnetlink.

Signed-off-by: Nicolas Dichtel <nicolas.dichtel@6wind.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/include/linux/netdevice.h b/include/linux/netdevice.h
index b4cfb63..f44f99a 100644
--- a/include/linux/netdevice.h
+++ b/include/linux/netdevice.h
@@ -2378,7 +2378,9 @@
 extern unsigned int	dev_get_flags(const struct net_device *);
 extern int		__dev_change_flags(struct net_device *, unsigned int flags);
 extern int		dev_change_flags(struct net_device *, unsigned int);
-extern void		__dev_notify_flags(struct net_device *, unsigned int old_flags);
+void			__dev_notify_flags(struct net_device *,
+					   unsigned int old_flags,
+					   unsigned int gchanges);
 extern int		dev_change_name(struct net_device *, const char *);
 extern int		dev_set_alias(struct net_device *, const char *, size_t);
 extern int		dev_change_net_namespace(struct net_device *,