platform/chrome: cros_ec_sysfs: switch to SPDX identifier

Adopt the SPDX license identifier headers to ease license compliance
management. Also change the description for one more appropriate.
Signed-off-by: NEnric Balletbo i Serra <enric.balletbo@collabora.com>
Reviewed-by: NGuenter Roeck <groeck@chromium.org>

drivers/platform/chrome/cros_ec_sysfs.c

-/*
- * cros_ec_sysfs - expose the Chrome OS EC through sysfs
- *
- * Copyright (C) 2014 Google, Inc.
- *
- * This program is free software; you can redistribute it and/or modify
- * it under the terms of the GNU General Public License as published by
- * the Free Software Foundation; either version 2 of the License, or
- * (at your option) any later version.
- *
- * This program is distributed in the hope that it will be useful,
- * but WITHOUT ANY WARRANTY; without even the implied warranty of
- * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
- * GNU General Public License for more details.
- *
- * You should have received a copy of the GNU General Public License
- * along with this program. If not, see <http://www.gnu.org/licenses/>.
- */
+// SPDX-License-Identifier: GPL-2.0+
+// Expose the ChromeOS EC through sysfs
+//
+// Copyright (C) 2014 Google, Inc.
 
 #define pr_fmt(fmt) "cros_ec_sysfs: " fmt
 
@@ -389,5 +375,5 @@ static struct platform_driver cros_ec_sysfs_driver = {
 module_platform_driver(cros_ec_sysfs_driver);
 
 MODULE_LICENSE("GPL");
-MODULE_DESCRIPTION("ChromeOS EC control driver");
+MODULE_DESCRIPTION("Expose the ChromeOS EC through sysfs");
 MODULE_ALIAS("platform:" DRV_NAME);