ACPI / PMIC: Add opregion driver for Intel CHT Whiskey Cove PMIC

Add opregion driver for Intel CHT Whiskey Cove PMIC, based on various
non upstreamed CHT Whiskey Cove PMIC patches. This does not include
support for the Thermal opregion (DPTF) due to lacking documentation.

Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>