dmaengine: at_xdmac: Use devm_platform_ioremap_resource() in at_xdmac_probe()

Simplify this function implementation by using a known wrapper function.

This issue was detected by using the Coccinelle software.

Signed-off-by: Markus Elfring <elfring@users.sourceforge.net>
Acked-by: Ludovic Desroches <ludovic.desroches@microchip.com>
Link: https://lore.kernel.org/r/377247f3-b53a-a9d9-66c7-4b8515de3809@web.de


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