bus: imx-weim: use devm_platform_ioremap_resource

devm_platform_get_and_ioremap_resource maps a resource and returns its
physical address. If we don't need the physical address, we should call
devm_platform_ioremap_resource instead.

Signed-off-by: Martin Kaiser <martin@kaiser.cx>
Signed-off-by: Shawn Guo <shawnguo@kernel.org>