acpi: Support writing Device Properties objects via _DSD
More complex device properties can be provided to drivers via a
device-specific data (_DSD) object.
To create this we need to build it up in a separate data structure and
then generate the ACPI code, due to its recursive nature.
Add an implementation of this.
Signed-off-by: Simon Glass <sjg@chromium.org> Reviewed-by: Wolfgang Wallner <wolfgang.wallner@br-automation.com> Reviewed-by: Bin Meng <bmeng.cn@gmail.com>