mmc: au1xmmc: switch to platform_get_irq

platform_get_resource(pdev, IORESOURCE_IRQ) is not recommended for
requesting IRQ's resources, as they can be not ready yet. Using
platform_get_irq() instead is preferred for getting IRQ even if it
was not retrieved earlier.

Signed-off-by: Yangtao Li <tiny.windzz@gmail.com>
Link: https://lore.kernel.org/r/20191215175120.3290-13-tiny.windzz@gmail.com


Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>