gpio: mxs: Switch to SPDX identifier

Adopt the SPDX license identifier headers to ease license compliance
management.

Signed-off-by: Fabio Estevam <fabio.estevam@nxp.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>

drivers/gpio/gpio-mxs.c

@@ -1,24 +1,10 @@
-/*
- * MXC GPIO support. (c) 2008 Daniel Mack <daniel@caiaq.de>
- * Copyright 2008 Juergen Beisert, kernel@pengutronix.de
- *
- * Based on code from Freescale,
- * Copyright (C) 2004-2010 Freescale Semiconductor, Inc. All Rights Reserved.
- *
- * 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, write to the Free Software
- * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston,
- * MA  02110-1301, USA.
- */
+// SPDX-License-Identifier: GPL-2.0+
+//
+// MXC GPIO support. (c) 2008 Daniel Mack <daniel@caiaq.de>
+// Copyright 2008 Juergen Beisert, kernel@pengutronix.de
+//
+// Based on code from Freescale,
+// Copyright (C) 2004-2010 Freescale Semiconductor, Inc. All Rights Reserved.
 
 #include <linux/err.h>
 #include <linux/init.h>