Return PciRootBridges instead of NULL and set PcdPciDisableBusEnumeration to FALSE when root bridge count is zero. Reviewed-by: Guo Dong <guo.dong@intel.com> Reviewed-by: Gua Guo <gua.guo@intel.com> Signed-off-by: Kavya <k.kavyax.sravanthi@intel.com>