dmaengine: jz4780: Use devm_platform_ioremap_resource() in jz4780_dma_probe()

Simplify this function implementation a bit by using
a known wrapper function.

This issue was detected by using the Coccinelle software.

Signed-off-by: Markus Elfring <elfring@users.sourceforge.net>
Link: https://lore.kernel.org/r/5dd19f28-349a-4957-ea3a-6aebbd7c97e2@web.de


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