pinctrl: berlin: switch to SPDX license identifier

Use the appropriate SPDX license identifier in the berlin pinctrl
driver source file and drop the previous license text.

Signed-off-by: Jisheng Zhang <Jisheng.Zhang@synaptics.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
diff --git a/drivers/pinctrl/berlin/berlin-bg2cd.c b/drivers/pinctrl/berlin/berlin-bg2cd.c
index 9bee7bd..c0f5d86 100644
--- a/drivers/pinctrl/berlin/berlin-bg2cd.c
+++ b/drivers/pinctrl/berlin/berlin-bg2cd.c
@@ -1,13 +1,10 @@
+// SPDX-License-Identifier: GPL-2.0
 /*
  * Marvell Berlin BG2CD pinctrl driver.
  *
  * Copyright (C) 2014 Marvell Technology Group Ltd.
  *
  * Antoine Ténart <antoine.tenart@free-electrons.com>
- *
- * This file is licensed under the terms of the GNU General Public
- * License version 2. This program is licensed "as is" without any
- * warranty of any kind, whether express or implied.
  */
 
 #include <linux/init.h>