How to Hide the "Hide/Show Admin Bar" Admin Menu

function plt_hide_hide_admin_bar_from_front_end_menus() {
	//Hide the "Settings → Hide/Show Admin Bar" menu.
	remove_submenu_page('options-general.php', 'hide_admin_bar_from_front_end');
}

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

Where do I put this code?