ACPI spec 5 defined the _ADR encoding for sdio bus as:
High word - slot number (0 based)
Low word  - function number

This patch adds support for binding sdio function device with acpi node,
and if successful, involve acpi into its power management.
Signed-off-by: Aaron Lu <aaron.lu@intel.com>
Reviewed-by: Adrian Hunter <adrian.hunter@intel.com>
Signed-off-by: Chris Ball <cjb@laptop.org>