[L] Change in coreboot[main]: acpi: Add PPTT support

[David Milosevic (Code Review)]

Attention is currently required from: Arthur Heymans, Cliff Huang, Lance Zhao, Martin L Roth, Maximilian Brune, Nico Huber, Patrick Rudolph, Tim Wawrzynczak.

David Milosevic has posted comments on this change. ( https://review.coreboot.org/c/coreboot/+/78071?usp=email )

Change subject: acpi: Add PPTT support
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Patch Set 18:

(1 comment)

File src/acpi/acpi_pptt.c:

https://review.coreboot.org/c/coreboot/+/78071/comment/a4266729_e15b5894 :
PS17, Line 74: u32 *n_caches
> Thought about this, but then we would have to add an additional element as terminator at the end. […]

Forgot to mention, that we also need "n_caches" to index into "cache_refs". Sure, we could pass a pointer to the next free slot within "cache_refs" instead of a pointer to the base of it. But then again, we still need the base pointer in order to search the buffer in "reference_for_cache".

I really would like to remove "n_caches" but I cant find a better solution. What do you think?