Use devm_platform_ioremap_resource_byname() to simplify the code.

Link: https://lore.kernel.org/r/20200916084017.14086-1-huobean@gmail.comAcked-by: Alim Akhtar <alim.akhtar@samsung.com>
Signed-off-by: Bean Huo <beanhuo@micron.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>