vDPA supports the possibility to use user VA in the iotlb messages. So, let's add support for user VA in vringh to use it in the vDPA simulators. Acked-by: Eugenio Pérez <eperezma@redhat.com> Signed-off-by: Stefano Garzarella <sgarzare@redhat.com> Message-Id: <20230404131716.45855-1-sgarzare@redhat.com> Signed-off-by: Michael S. Tsirkin <mst@redhat.com>