How to Hide VoxFor Mega Menu Pro Admin Menus

function plt_hide_voxfor_mega_menu_menus() {
	//Hide "Mega Menu".
	remove_menu_page('voxfor-mega-menu');
	//Hide "Mega Menu → All Mega Menus".
	remove_submenu_page('voxfor-mega-menu', 'voxfor-mega-menu');
	//Hide "Mega Menu → Add New Menu".
	remove_submenu_page('voxfor-mega-menu', 'voxfor-mega-menu-builder');
	//Hide "Mega Menu → Settings".
	remove_submenu_page('voxfor-mega-menu', 'voxfor-mega-menu-settings');
}

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

Where do I put this code?