Change in coreboot[master]: libpayload/pci: Split PCI interfaces as common and chip related

[Jianjun Wang (Code Review)]

Attention is currently required from: Shelley Chen, Hung-Te Lin, Angel Pons, Yu-Ping Wu.
Jianjun Wang has posted comments on this change. ( https://review.coreboot.org/c/coreboot/+/56789 )

Change subject: libpayload/pci: Split PCI interfaces as common and chip related
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Patch Set 37:

(1 comment)

Commit Message:

https://review.coreboot.org/c/coreboot/+/56789/comment/488a0380_67129793 
PS37, Line 7: libpayload/pci: Split PCI interfaces as common and chip related
> libpayload/pci: Add support for MMIO

Can we use "Add support for map bus"? It's more like we are adding map bus feature in this change.
MMIO sounds more like the ECAM that accesses the configuration space through MMIO space.