fixed missing prefs.php require_once to use getPref in line 79

src/validate.php

@@ -14,6 +14,7 @@ session_start();
 require_once('../functions/i18n.php');
 require_once('../functions/auth.php');
 require_once('../functions/strings.php');
+require_once('../functions/prefs.php');
 
 is_logged_in();
 
@@ -84,4 +85,4 @@ if ( $timeZone != SMPREF_NONE && ($timeZone <> '')
     putenv( 'TZ=' . $timeZone );
 }
 
-?>
+?>