PciConfigIo is a legacy pci bus dispatcher, which manages all pci
devices including a pci root bridge. However, it is unnecessary to
design a complex hierarchy which redirects every access by PciRoot.
Since pci root bridge is also a pci device instance, and only contains
easy config space read/write, and PciConfigIo actually acts as a pci bus
to dispatch resource based resolving when VMExit, we re-arrange to make
the pci hierarchy clean.
Signed-off-by: Jing Liu <jing2.liu@linux.intel.com>