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

[Nico Huber (Code Review)]

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

Nico Huber 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 9:

(1 comment)

File src/acpi/acpi_pptt.c:

https://review.coreboot.org/c/coreboot/+/78071/comment/71b8aa60_0414f1f5 :
PS6, Line 113: for (struct pptt_cpu_resources *it = root->resources; it != NULL; it = it->next)
             : 		pptt_cpu_push_resource(cpu_idx, r_idx++, new_pptt_cache(current, it->cache, pptt), pptt);
> The position (current) of the new cache entry (new_pptt_cache) depends on the number of resources we […]

Took me a moment to understand what "size to alloc" means in this case. It's
`*current` that needs to be increased *before* we can place the resources. So
counting in advance is indeed necessary, unless we'd want to put things into
a secondary buffer first (w/ probably worse complexity).