[NETNS]: Namespacing in the generic fib rules code.

Move static rules_ops & rules_mod_lock to the struct net, register the
pernet subsys to init them and enjoy the fact that the core rules
infrastructure works in the namespace.

Real IPv4 fib rules virtualization requires fib tables support in the
namespace and will be done seriously later in the patchset.

Acked-by: Benjamin Thery <benjamin.thery@bull.net>
Acked-by: Daniel Lezcano <dlezcano@fr.ibm.com>
Signed-off-by: Denis V. Lunev <den@openvz.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/include/net/net_namespace.h b/include/net/net_namespace.h
index b0a5f90..b8c1d60 100644
--- a/include/net/net_namespace.h
+++ b/include/net/net_namespace.h
@@ -40,6 +40,10 @@
 	struct hlist_head 	*dev_name_head;
 	struct hlist_head	*dev_index_head;
 
+	/* core fib_rules */
+	struct list_head	rules_ops;
+	spinlock_t		rules_mod_lock;
+
 	struct sock 		*rtnl;			/* rtnetlink socket */
 
 	/* core sysctls */