gossipd: fix memleak false-positive

2019-09-26T02:00:47.832Z DEBUG lightning_hsmd(89822): Client: Received message 33 from client'
2019-09-26T02:00:47.837Z **BROKEN** lightning_gossipd(89828): MEMLEAK: 0x55eddc5d1fd8
2019-09-26T02:00:47.838Z **BROKEN** lightning_gossipd(89828):   label=gossipd/routing.c:1579:struct unupdated_channel
2019-09-26T02:00:47.838Z DEBUG lightning_gossipd(89828):   backtrace:
2019-09-26T02:00:47.838Z DEBUG lightning_gossipd(89828):     ccan/ccan/tal/tal.c:437 (tal_alloc_)
2019-09-26T02:00:47.838Z DEBUG lightning_gossipd(89828):     gossipd/routing.c:1579 (routing_add_channel_announcement)
2019-09-26T02:00:47.838Z DEBUG lightning_gossipd(89828):     gossipd/routing.c:1867 (handle_pending_cannouncement)
2019-09-26T02:00:47.838Z DEBUG lightning_gossipd(89828):     gossipd/gossipd.c:1543 (handle_txout_reply)
2019-09-26T02:00:47.838Z DEBUG lightning_gossipd(89828):     gossipd/gossipd.c:1726 (recv_req)
2019-09-26T02:00:47.838Z DEBUG lightning_gossipd(89828):     common/daemon_conn.c:31 (handle_read)
2019-09-26T02:00:47.838Z DEBUG lightning_gossipd(89828):     ccan/ccan/io/io.c:59 (next_plan)
2019-09-26T02:00:47.838Z DEBUG lightning_gossipd(89828):     ccan/ccan/io/io.c:407 (do_plan)

Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>

gossipd/routing.c

@@ -223,6 +223,7 @@ static void memleak_help_routing_tables(struct htable *memtable,
 	memleak_remove_htable(memtable, &rstate->pending_node_map->raw);
 	memleak_remove_htable(memtable, &rstate->pending_cannouncements.raw);
 	memleak_remove_htable(memtable, &rstate->local_chan_map.raw);
+	memleak_remove_uintmap(memtable, &rstate->unupdated_chanmap);
 
 	for (n = node_map_first(rstate->nodes, &nit);
 	     n;