pinctrl: mediatek: use devm_platform_ioremap_resource_byname()

Use the devm_platform_ioremap_resource_byname() helper instead of
calling platform_get_resource_byname() and devm_ioremap_resource()
separately.

Signed-off-by: Wang Xiaojun <wangxiaojun11@huawei.com>
Acked-by: Sean Wang <sean.wang@kernel.org>
Link: https://lore.kernel.org/r/20200917064151.2184010-1-wangxiaojun11@huawei.com


Signed-off-by: Linus Walleij <linus.walleij@linaro.org>