PCI: controller: Convert to devm_platform_ioremap_resource()

Use devm_platform_ioremap_resource() to simplify the code, since t
contains platform_get_resource() and devm_ioremap_resource() calls
respectively.

Link: https://lore.kernel.org/r/20200708155614.308-1-zhengdejin5@gmail.com


Signed-off-by: Dejin Zheng <zhengdejin5@gmail.com>
Signed-off-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>
Reviewed-by: Rob Herring <robh@kernel.org>