Allow change Price for product on POS panel

/**
 * Plugin Name: WooCommerce Smart Coupons
 * Plugin URI: https://woocommerce.com/products/smart-coupons/
 * Description: <strong>WooCommerce Smart Coupons</strong> lets customers buy gift certificates, store credits or coupons easily. They can use purchased credits themselves or gift to someone else.
 * Version: 3.9.1
 * Author: StoreApps
 * Author URI: https://www.storeapps.org/
 * Developer: StoreApps
 * Developer URI: https://www.storeapps.org/
 * Requires at least: 4.4
 * Tested up to: 4.9.9
 * WC requires at least: 2.5.0
 * WC tested up to: 3.5.3
 * Text Domain: woocommerce-smart-coupons
 * Domain Path: /languages
 * Woo: 18729:05c45f2aa466106a466de4402fff9dde
 * Copyright (c) 2014-2019 WooCommerce, StoreApps All rights reserved.
 * License: GNU General Public License v3.0
 * License URI: http://www.gnu.org/licenses/gpl-3.0.html
 *
 * @package woocommerce-smart-coupons
 */