How to Hide the "Fast Velocity Minify" Admin Menu

function plt_hide_fast_velocity_minify_menus() {
	//Hide the "Settings → Fast Velocity Minify" menu.
	remove_submenu_page('options-general.php', 'fastvelocity-min');
}

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

Where do I put this code?