Impliment the vhost-crypto's funtions, such as startup,
stop and notification etc. Introduce an enum
QCryptoCryptoDevBackendOptionsType in order to
identify the cryptodev vhost backend is vhost-user
or vhost-kernel-module (If exist).

At this point, the cryptdoev-vhost-user works.
Signed-off-by: NGonglei <arei.gonglei@huawei.com>
Signed-off-by: NLongpeng(Mike) <longpeng2@huawei.com>
Signed-off-by: NJay Zhou <jianjay.zhou@huawei.com>
Reviewed-by: NMichael S. Tsirkin <mst@redhat.com>
Signed-off-by: NMichael S. Tsirkin <mst@redhat.com>