Update add_code.php

The new codes in yasDB_clean dosent work with embed codes
I did an if statement for '($_POST['code'])' but captcha use the same name so i cant use it

but what I do know is add code safe in the admin panel, if not I can make a custom function for add code

New code bellow
$dirty = strip_tags($dirty);
$dirty = htmlspecialchars($dirty);