Simplify resource mapping by using devm_platform_ioremap_resource()
instead of the longer devm_platform_get_and_ioremap_resource() helper
as the last argument is NULL.
Additionally, use platform_get_irq() to retrieve the interrupt
instead of irq_of_parse_and_map() and propagate its error code on
failure. irq_of_parse_and_map() requires irq_dispose_mapping, which is
missing.