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

[Felix Held (Code Review)]

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

Felix Held has posted comments on this change. ( https://review.coreboot.org/c/coreboot/+/79927?usp=email )

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

(1 comment)

File src/include/device/pci_def.h:

https://review.coreboot.org/c/coreboot/+/79927/comment/cb6fcf3e_e731874f :
PS2, Line 594: #define PCI_BUS_NUMBER_MASK		0xff
             : #define PCI_SEGMENT_GROUP_COUNT		((CONFIG_ECAM_MMCONF_BUS_NUMBER >> 8) + 1)
             : #define PCI_BUSES_PER_SEGMENT_GROUP	(((CONFIG_ECAM_MMCONF_BUS_NUMBER - 1) & PCI_BUS_NUMBER_MASK) + 1)
             : #define PCI_PER_SEGMENT_GROUP_ECAM_SIZE	(256 * MiB)
not sure about those names yet; if you have some better suggestion, please tell