gpio: lynxpoint: Convert to use SPDX identifier

Reduce size of duplicated comments by switching to use SPDX identifier.

No functional change.
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>

drivers/gpio/gpio-lynxpoint.c

+// SPDX-License-Identifier: GPL-2.0
 /*
  * GPIO controller driver for Intel Lynxpoint PCH chipset>
  * Copyright (c) 2012, Intel Corporation.
  *
  * Author: Mathias Nyman <mathias.nyman@linux.intel.com>
- *
- * This program is free software; you can redistribute it and/or modify it
- * under the terms and conditions of the GNU General Public License,
- * version 2, as published by the Free Software Foundation.
- *
- * This program is distributed in the hope 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, write to the Free Software Foundation, Inc.,
- * 51 Franklin St - Fifth Floor, Boston, MA 02110-1301 USA.
- *
  */
 
 #include <linux/acpi.h>
@@ -468,5 +455,5 @@ module_exit(lp_gpio_exit);
 
 MODULE_AUTHOR("Mathias Nyman (Intel)");
 MODULE_DESCRIPTION("GPIO interface for Intel Lynxpoint");
-MODULE_LICENSE("GPL");
+MODULE_LICENSE("GPL v2");
 MODULE_ALIAS("platform:lp_gpio");