Support quick retries by deleting Ortho4XP with distclean only

Makefile.tiles

@@ -163,14 +163,14 @@ $(ZIPS): z_%.zip: z_%
 
 clean:
 	@echo [$@]
-	-rm -rf Ortho4XP
 	-rm -rf var/run
 	-rm -f $(ZIPS)
 	-rm -rf z_$(TILENAME)*
 	-rm -f $(TILENAME)_tile_list.*
 
 distclean: clean
 	@echo [$@]
+	-rm -rf Ortho4XP
 	-rm -rf var
 	-rm -f z_*
 	-rm -f *_tile_list.*