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>
6 files changed