xfrm: Register xfrm_dev_notifier in appropriate place

Currently, driver registers it from pernet_operations::init method,
and this breaks modularity, because initialization of net namespace
and netdevice notifiers are orthogonal actions. We don't have
per-namespace netdevice notifiers; all of them are global for all
devices in all namespaces.

Signed-off-by: Kirill Tkhai <ktkhai@virtuozzo.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/include/net/xfrm.h b/include/net/xfrm.h
index aa027ba..a872379 100644
--- a/include/net/xfrm.h
+++ b/include/net/xfrm.h
@@ -1894,7 +1894,7 @@
 #endif
 }
 
-void __net_init xfrm_dev_init(void);
+void __init xfrm_dev_init(void);
 
 #ifdef CONFIG_XFRM_OFFLOAD
 void xfrm_dev_resume(struct sk_buff *skb);