[pvmfw][virtio] Refactor PCI initialisation am: 287de62468 am: c286e15e6a

Original change: https://android-review.googlesource.com/c/platform/packages/modules/Virtualization/+/2617394

Change-Id: I922ffabf9e7b4eaed9ff3b2adba955e1da372d25
Signed-off-by: Automerger Merge Worker <android-build-automerger-merge-worker@system.gserviceaccount.com>