[IPV4]: Prepare FIB core for RCU.

* RCU versions of hlist_***_rcu
* fib_alias partial rcu port just whats needed now.

Signed-off-by: Robert Olsson <Robert.Olsson@data.slu.se>
Signed-off-by: Stephen Hemminger <shemminger@osdl.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/net/ipv4/fib_lookup.h b/net/ipv4/fib_lookup.h
index b729d97..ef6609e 100644
--- a/net/ipv4/fib_lookup.h
+++ b/net/ipv4/fib_lookup.h
@@ -7,6 +7,7 @@
 
 struct fib_alias {
 	struct list_head	fa_list;
+	struct rcu_head rcu;
 	struct fib_info		*fa_info;
 	u8			fa_tos;
 	u8			fa_type;