Use devm_platform_ioremap_resource() to simplify code.
Signed-off-by: Yangtao Li <tiny.windzz@gmail.com>
Link: https://lore.kernel.org/r/20191215175120.3290-7-tiny.windzz@gmail.comSigned-off-by: Ulf Hansson <ulf.hansson@linaro.org>