Change in coreboot[master]: mb/google/guybrush: Add support to override dxio port descriptors

[Martin Roth (Code Review)]

Attention is currently required from: Furquan Shaikh, Karthik Ramasubramanian.
Martin Roth has posted comments on this change. ( https://review.coreboot.org/c/coreboot/+/55599 )

Change subject: mb/google/guybrush: Add support to override dxio port descriptors
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Patch Set 4: Code-Review-2

(1 comment)

Patchset:

PS4: 
This isn't currently needed since we're moving the PCIe resets out of the dxio descriptors.

Following my understanding of best practices, I think that this should probably be abandoned until it's actually needed.