Fix train braking model not being set to original on load

src/saveload/afterload.cpp

@@ -3830,6 +3830,10 @@ bool AfterLoadGame()
 		UpdateAllAnimatedTileSpeeds();
 	}
 
+	if (SlXvIsFeatureMissing(XSLFI_REALISTIC_TRAIN_BRAKING)) {
+		_settings_game.vehicle.train_braking_model = TBM_ORIGINAL;
+	}
+
 	if (SlXvIsFeatureMissing(XSLFI_INFLATION_FIXED_DATES)) {
 		_settings_game.economy.inflation_fixed_dates = !IsSavegameVersionBefore(SLV_GS_INDUSTRY_CONTROL);
 	}