How to Hide Page for Random Banners Admin Menus

function plt_hide_page_for_random_banners_menus() {
	//Hide the "Page for Random Banners" menu.
	remove_menu_page('edit.php?post_type=rl_pfrb_headerfooter');
	//Hide the "Page for Random Banners → Page for Random Banners" menu.
	remove_submenu_page('edit.php?post_type=rl_pfrb_headerfooter', 'edit.php?post_type=rl_pfrb_headerfooter');
	//Hide the "Page for Random Banners → Add a New Page for Random Banners" menu.
	remove_submenu_page('edit.php?post_type=rl_pfrb_headerfooter', 'post-new.php?post_type=rl_pfrb_headerfooter');
}

add_action('admin_menu', 'plt_hide_page_for_random_banners_menus', 15);

Where do I put this code?