Network: Include town noise levels in network game saves

Don't recalculate on load for network clients

src/station_cmd.cpp

@@ -70,6 +70,8 @@
 
 #include "safeguards.h"
 
+bool _town_noise_no_update = false;
+
 /**
  * Check whether the given tile is a hangar.
  * @param t the tile to of whether it is a hangar.
@@ -2639,6 +2641,8 @@ Town *AirportGetNearestTown(const AirportSpec *as, TileIndex tile, const TileIte
 /** Recalculate the noise generated by the airports of each town */
 void UpdateAirportsNoise()
 {
+	if (_town_noise_no_update) return;
+
 	for (Town *t : Town::Iterate()) t->noise_reached = 0;
 
 	for (const Station *st : Station::Iterate()) {