tipc: fix a missing rhashtable_walk_exit()

rhashtable_walk_exit() must be paired with rhashtable_walk_enter().

Fixes: 40f9f439 ("tipc: Fix tipc_sk_reinit race conditions")
Cc: Herbert Xu <herbert@gondor.apana.org.au>
Cc: Ying Xue <ying.xue@windriver.com>
Signed-off-by: NCong Wang <xiyou.wangcong@gmail.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

net/tipc/socket.c

@@ -2672,6 +2672,8 @@ void tipc_sk_reinit(struct net *net)
 
 		rhashtable_walk_stop(&iter);
 	} while (tsk == ERR_PTR(-EAGAIN));
+
+	rhashtable_walk_exit(&iter);
 }
 
 static struct tipc_sock *tipc_sk_lookup(struct net *net, u32 portid)