net,rcu: convert call_rcu(__leaf_info_free_rcu) to kfree_rcu()

The rcu callback __leaf_info_free_rcu() just calls a kfree(),
so we use kfree_rcu() instead of the call_rcu(__leaf_info_free_rcu).
Signed-off-by: Lai Jiangshan <laijs@cn.fujitsu.com>
Acked-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Reviewed-by: Josh Triplett <josh@joshtriplett.org>

net/ipv4/fib_trie.c

@@ -350,14 +350,9 @@ static inline void free_leaf(struct leaf *l)
 	call_rcu_bh(&l->rcu, __leaf_free_rcu);
 }
 
-static void __leaf_info_free_rcu(struct rcu_head *head)
-{
-	kfree(container_of(head, struct leaf_info, rcu));
-}
-
 static inline void free_leaf_info(struct leaf_info *leaf)
 {
-	call_rcu(&leaf->rcu, __leaf_info_free_rcu);
+	kfree_rcu(leaf, rcu);
 }
 
 static struct tnode *tnode_alloc(size_t size)