How to Hide the "Safelayout Preloader" Admin Menu

function plt_hide_safelayout_cute_preloader_menus() {
	//Hide the "Settings → Safelayout Preloader" menu.
	remove_submenu_page('options-general.php', 'safelayout-cute-preloader');
}

add_action('admin_menu', 'plt_hide_safelayout_cute_preloader_menus', 11);

Where do I put this code?