Change in coreboot[master]: mb/google/guybrush: Add initial fch irq routing

[Kyösti Mälkki (Code Review)]

Attention is currently required from: Raul Rangel, Martin Roth, Mathew King, Felix Held.
Kyösti Mälkki has posted comments on this change. ( https://review.coreboot.org/c/coreboot/+/51473 )

Change subject: mb/google/guybrush: Add initial fch irq routing
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Patch Set 3:

(1 comment)

File src/mainboard/google/guybrush/mainboard.c:

https://review.coreboot.org/c/coreboot/+/51473/comment/fde60c41_f417ca2a 
PS3, Line 20:
> I would ideally like to see this table defined in device tree. […]

I won't -2 this one. But I'd like to see Felix ack this with his +2, as it appears he has taken some ownership of soc/amd/common management and deduplication work. And this will be one more copy to his assignments.

Should older AGESA and binaryPI survive through next release (May 2021), someone probably takes interest in such finalized IRQ API. CB:38564.