lua: disable readline if package is not enabled or on stage 0

lua/lua/lua.conf

@@ -16,6 +16,11 @@
 # we patch in autotools support
 autogen=1
 
+# packages support
+if atstage toolchain || ! pkginstalled readline; then
+	var_append extraconfopt ' ' '--without-readline'
+fi
+
 # create missing directories
 lua_postmake() {
 	for x in "$lualibdir" "$luadatadir"; do