[M] Change in coreboot[main]: device: Add support for multiple PCI segment groups

[Nico Huber (Code Review)]

Attention is currently required from: Cliff Huang, Felix Held, Fred Reitberger, Jason Glenesk, Lance Zhao, Matt DeVillier, Patrick Rudolph, Tim Wawrzynczak.

Nico Huber has posted comments on this change. ( https://review.coreboot.org/c/coreboot/+/79877?usp=email )

Change subject: device: Add support for multiple PCI segment groups
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Patch Set 2:

(1 comment)

File src/acpi/acpi.c:

https://review.coreboot.org/c/coreboot/+/79877/comment/98d5fd6d_615da305 :
PS1, Line 157: i * CONFIG_ECAM_MMCONF_BUS_NUMBER
> Would it be possible to iterate over all devices of type PATH_DOMAIN and use bus->subordinate , bus- […]

I assume that would alter how things are numbered in Linux (i.e. more PCI domains)
and that could confuse people. Only technical issue I can think of is if some
code assumes ECAM to be naturally aligned (I don't think that's demanded by the
standard, but we should better check).