[coreboot-gerrit] Change in coreboot[master]: apple/macbook21: configure the clockgen and add C3 CPU state

[Nico Huber (Code Review)]

Attention is currently required from: Ferass EL HAFIDI, Paul Menzel, Arthur Heymans, Evgeny Zinoviev, Felix Held.
Nico Huber has posted comments on this change. ( https://review.coreboot.org/c/coreboot/+/63587 )

Change subject: apple/macbook21: configure the clockgen and add C3 CPU state
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Patch Set 6:

(2 comments)

Patchset:

PS6: 
Was the latest version tested? It seems `config OVERRIDE_DEVICETREE`
is missing.

File src/mainboard/apple/macbook21/cstates.c:

https://review.coreboot.org/c/coreboot/+/63587/comment/228c4db4_896cbc64 
PS4, Line 34: 		.latency = 17,
> Only because you do not experience any problems with your use cases, this does not have to be the co […]

This was before Intel published much information about the matter, AFAICS.
I'm not sure if there is a correct value, but suggestions how to figure one
out are welcome of course.