Change in coreboot[master]: acpi: Add function for adding board-specific support to SSDT

[Cliff Huang (Code Review)]

Attention is currently required from: Bora Guvendik, Nico Huber, Selma Bensaid, Tim Wawrzynczak, Paul Menzel.
Cliff Huang has posted comments on this change. ( https://review.coreboot.org/c/coreboot/+/61884 )

Change subject: acpi: Add function for adding board-specific support to SSDT
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Patch Set 2:

(1 comment)

Patchset:

PS2:
> What do you mean by "get the list of all devices"? That list is global. […]

Yes. you're correct. The intension to to get the global list. Please see another review on how it actual being used: https://review.coreboot.org/c/coreboot/+/61887/5/src/mainboard/google/brya/v.... Note that since this access global list. Therefore, mainboard only provides the function definition but it is actually called in acpi.c.