/*
 * Register portfolio fields post type
 */
function add_portfolio_img_post_type() {
    register_post_type('add_portfolio_img', array(
        'public' => true,
        'labels' => array(
            'name' => __('Картинки портфолио')
        )
    ));
}
add_action('init', 'add_portfolio_img_post_type');