Use devm_platform_ioremap_resource to simplify code

Signed-off-by: Chunfeng Yun <chunfeng.yun@mediatek.com>
Reviewed-by: Peter Chen <peter.chen@nxp.com>
Link: https://lore.kernel.org/r/1604642930-29019-5-git-send-email-chunfeng.yun@mediatek.com


Signed-off-by: Vinod Koul <vkoul@kernel.org>