Change the PciBusDxe driver to install the PCI enumeration complete GUID in the PCI host bridge handle to follow PI Spec 1.3.

Signed-off-by: Ruiyu Ni <ruiyu.ni@intel.com>
Reviewed-by: Elvin Li <elvin.li@intel.com>

git-svn-id: https://svn.code.sf.net/p/edk2/code/trunk/edk2@14553 6f19259b-4bc3-4df7-8a09-765794883524