gossip queries: patch up valgrind errors in tests

These were giving me valgrind errors locally; fixed now.

gossipd/gossipd.c

@@ -360,6 +360,8 @@ static bool encoding_end_zlib(u8 **encoded, size_t off)
 	/* Successful: copy over and trim */
 	tal_resize(encoded, off + tal_count(z));
 	memcpy(*encoded + off, z, tal_count(z));
+
+	tal_free(z);
 	return true;
 }
 

gossipd/test/run-extended-info.c

@@ -602,6 +602,7 @@ static u8 *test_query_channel_range(const char *test_vector, const jsmntok_t *ob
 	}
 	msg = towire_query_channel_range(NULL, &chain_hash, firstBlockNum, numberOfBlocks, tlvs);
 
+	tal_free(tlvs);
 	return msg;
 }
 
@@ -613,15 +614,17 @@ static u8 *test_reply_channel_range(const char *test_vector, const jsmntok_t *ob
 	size_t i;
 	u8 *msg;
 	u8 *encoded_scids;
+
+	u8 *ctx = tal(NULL, u8);
 	struct tlv_reply_channel_range_tlvs *tlvs
-		= tlv_reply_channel_range_tlvs_new(NULL);
+		= tlv_reply_channel_range_tlvs_new(ctx);
 
 	get_chainhash(test_vector, obj, &chain_hash);
 	assert(json_to_number(test_vector, json_get_member(test_vector, obj, "firstBlockNum"), &firstBlockNum));
 	assert(json_to_number(test_vector, json_get_member(test_vector, obj, "numberOfBlocks"), &numberOfBlocks));
 	assert(json_to_number(test_vector, json_get_member(test_vector, obj, "complete"), &complete));
 
-	encoded_scids = get_scid_array(NULL, test_vector, obj);
+	encoded_scids = get_scid_array(ctx, test_vector, obj);
 
 	opt = json_get_member(test_vector, obj, "timestamps");
 	if (opt) {
@@ -686,7 +689,7 @@ static u8 *test_reply_channel_range(const char *test_vector, const jsmntok_t *ob
 	msg = towire_reply_channel_range(
 		NULL, &chain_hash, firstBlockNum, numberOfBlocks,
 		complete, encoded_scids, tlvs);
-	tal_free(tlvs);
+	tal_free(ctx);
 	return msg;
 }