Change in coreboot[master]: soc/amd/common/block/rtd3: Add AMD specific RTD3 driver

[Raul Rangel (Code Review)]

Attention is currently required from: Jason Glenesk, Marshall Dawson, Tim Wawrzynczak, Karthik Ramasubramanian, Felix Held.
Raul Rangel has posted comments on this change. ( https://review.coreboot.org/c/coreboot/+/54966 )

Change subject: soc/amd/common/block/rtd3: Add AMD specific RTD3 driver
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Patch Set 1:

(1 comment)

File src/soc/amd/common/block/rtd3/rtd3.c:

https://review.coreboot.org/c/coreboot/+/54966/comment/85110049_dbd16d4b 
PS1, Line 109: Name (_PR2, Package (0x01)  // _PR2: Power Resources for D2
             :  *            {
             :  *                RTD3
             :  *            })
Not for linux, the reason I added it was:
https://docs.microsoft.com/en-us/windows-hardware/drivers/bringup/firmware-r...
> _PR2: This object evaluates to the device's power requirements in the D2 device power state. The return value is the list of power resources that the device requires in the D2 state. Note that for historical reasons, Windows expects _PR2 to be present whenever _PR0 is present. If D2 is implemented in the hardware, _PR2 lists the power resources needed for D2. If D2 is not implemented, _PR2 lists the same resources as _PR0.

Using acpi_device_add_power_res seems like a cleaner approach though. I'll refactor.