ACPI: PM: s2idle: Add AMD support to handle _DSM

Initial support for S2Idle based on the Intel implementation [1] does not
work for AMD as the BIOS implementation for ACPI methods like the _DSM
are not standardized.

So, the way in which the UUID's were parsed and the ACPI packages were
retrieved out of the ACPI objects are not the same between Intel and AMD.

Add AMD support for S2Idle to parse the UUID, evaluate the
_DSM methods, prepare the Idle constraint list etc.

Link: https://uefi.org/sites/default/files/resources/Intel_ACPI_Low_Power_S0_Idle.pdf # [1]
Signed-off-by: Shyam Sundar S K <Shyam-sundar.S-k@amd.com>
[ rjw: Subject and changelog edits ]
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>