spi: rockchip-sfc: Use devm_platform_ioremap_resource()

Convert platform_get_resource(), devm_ioremap_resource() to a single
call to devm_platform_ioremap_resource(), as this is exactly what this
function does.

Signed-off-by: Yang Li <yang.lee@linux.alibaba.com>
Reviewed-by: Tudor Ambarus <tudor.ambarus@linaro.org>
Link: https://lore.kernel.org/r/20230329062450.58924-1-yang.lee@linux.alibaba.com
Signed-off-by: Mark Brown <broonie@kernel.org>