Safer level crossings: add setting to improve RV level crossing safety.

src/saveload/afterload.cpp

@@ -3386,6 +3386,14 @@ bool AfterLoadGame()
 		_settings_game.economy.day_length_factor = 1;
 	}
 
+	if (SlXvIsFeatureMissing(XSLFI_SAFER_CROSSINGS)) {
+		for (TileIndex t = 0; t < map_size; t++) {
+			if (IsLevelCrossingTile(t)) {
+				SetCrossingOccupiedByRoadVehicle(t, EnsureNoRoadVehicleOnGround(t).Failed());
+			}
+		}
+	}
+
 	/* Road stops is 'only' updating some caches */
 	AfterLoadRoadStops();
 	AfterLoadLabelMaps();