update.php & daemon: chdir to script directory using __FILE__ magic constant

update.php

@@ -2,7 +2,8 @@
 <?php
 	define('DISABLE_SESSIONS', true);
 
-	chdir(dirname($_SERVER['SCRIPT_NAME']));
+	chdir(dirname(__FILE__));
+
 	require_once "functions.php";
 	require_once "sanity_check.php";
 	require_once "config.php";

update_daemon2.php

@@ -4,6 +4,7 @@
 	// Some configurable variable may be found below.
 
 	declare(ticks = 1);
+	chdir(dirname(__FILE__));
 
 	define('DISABLE_SESSIONS', true);