When the device ID of the host bridge is unknown, check if we are running as a PVH guest as there is no PCI bus in that case. Ref: https://bugzilla.tianocore.org/show_bug.cgi?id=1689 Signed-off-by: Anthony PERARD <anthony.perard@citrix.com> Acked-by: Laszlo Ersek <lersek@redhat.com> Message-Id: <20190813113119.14804-26-anthony.perard@citrix.com>