tipc: make three functions static

Fix the following sparse warning:

net/tipc/node.c:281:6: warning: symbol 'tipc_node_free' was not declared. Should it be static?
net/tipc/node.c:2801:5: warning: symbol '__tipc_nl_node_set_key' was not declared. Should it be static?
net/tipc/node.c:2878:5: warning: symbol '__tipc_nl_node_flush_key' was not declared. Should it be static?

Fixes: fc1b6d6d ("tipc: introduce TIPC encryption & authentication")
Fixes: e1f32190 ("tipc: add support for AEAD key setting via netlink")
Signed-off-by: Chen Wandun <chenwandun@huawei.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

net/tipc/node.c

@@ -278,7 +278,7 @@ struct tipc_crypto *tipc_node_crypto_rx_by_list(struct list_head *pos)
 }
 #endif
 
-void tipc_node_free(struct rcu_head *rp)
+static void tipc_node_free(struct rcu_head *rp)
 {
 	struct tipc_node *n = container_of(rp, struct tipc_node, rcu);
 
@@ -2798,7 +2798,7 @@ static int tipc_nl_retrieve_nodeid(struct nlattr **attrs, u8 **node_id)
 	return 0;
 }
 
-int __tipc_nl_node_set_key(struct sk_buff *skb, struct genl_info *info)
+static int __tipc_nl_node_set_key(struct sk_buff *skb, struct genl_info *info)
 {
 	struct nlattr *attrs[TIPC_NLA_NODE_MAX + 1];
 	struct net *net = sock_net(skb->sk);
@@ -2875,7 +2875,8 @@ int tipc_nl_node_set_key(struct sk_buff *skb, struct genl_info *info)
 	return err;
 }
 
-int __tipc_nl_node_flush_key(struct sk_buff *skb, struct genl_info *info)
+static int __tipc_nl_node_flush_key(struct sk_buff *skb,
+				    struct genl_info *info)
 {
 	struct net *net = sock_net(skb->sk);
 	struct tipc_net *tn = tipc_net(net);