Change: [Script] GetWaypointID to return the StationID of any waypoint

Modified ScriptWaypoint::GetWaypointID to also return the StationID of any waypoint (including road waypoint).

src/script/api/script_waypoint.cpp

@@ -24,8 +24,7 @@
 
 /* static */ StationID ScriptWaypoint::GetWaypointID(TileIndex tile)
 {
-	if (!ScriptRail::IsRailWaypointTile(tile) && !ScriptMarine::IsBuoyTile(tile)) return STATION_INVALID;
-
+	if (!::IsValidTile(tile) || !::IsTileType(tile, MP_STATION) || ::Waypoint::GetByTile(tile) == nullptr) return INVALID_STATION;
 	return ::GetStationIndex(tile);
 }