cryptodev backend interface is used to realize the active work for
virtual crypto device.
This patch only add the framework, doesn't include specific operations.
Signed-off-by: Gonglei <arei.gonglei@huawei.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
