ata: sata_dwc_460ex: Use devm_platform_*ioremap_resource() APIs

Use devm_platform_get_and_ioremap_resource() and
devm_platform_ioremap_resource() APIs instead of their
open coded analogues.

Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Damien Le Moal <damien.lemoal@opensource.wdc.com>