Change in coreboot[master]: sb/intel/common: Refactor _PRT generation to support GSI-based tables

[Tim Wawrzynczak (Code Review)]

Attention is currently required from: Nico Huber, Furquan Shaikh, Angel Pons, Patrick Rudolph.
Tim Wawrzynczak has posted comments on this change. ( https://review.coreboot.org/c/coreboot/+/50857 )

Change subject: sb/intel/common: Refactor _PRT generation to support GSI-based tables
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Patch Set 20:

(1 comment)

Commit Message:

https://review.coreboot.org/c/coreboot/+/50857/comment/76d1f687_2fb06779 
PS20, Line 13:
> Adding just as a placeholder to ensure this patch is tested before it can be submitted.

Good idea, thanks! Angel, Nico, Arthur, Patrick, etc. would be grateful if someone had a chance to test this on one of the existing `SOUTHBRIDGE_INTEL_COMMON_RCBA_PIRQ` platforms 😊