[M] Change in coreboot[master]: [WIP] soc/amd: Use ioapic helper functions

[Felix Held (Code Review)]

Attention is currently required from: Jason Glenesk, Raul Rangel, Marshall Dawson, Matt DeVillier, Kyösti Mälkki, Fred Reitberger.

Felix Held has posted comments on this change. ( https://review.coreboot.org/c/coreboot/+/55571 )

Change subject: [WIP] soc/amd: Use ioapic helper functions
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Patch Set 10: Code-Review+1

(2 comments)

Patchset:

PS1:
> it looks like that that info was only needed for generating the IVRS table back when it was generate […]

i'm not sure if fsp still uses the ioapic IDs; asked about this in an internal chat. in the current setup with an fch ioapic and a nb ioapic with the fch one always being number 0, we'll end up with the correct IDs

Patchset:

PS10: 
reviewed the code and ran a test on amd/mandolin and everything works and linux shows me the expected ioapic configuration in dmesg