This patch includes two parts: Cryptodev Backends
and virtio-crypto stuff. I can maintain cryptodev backends
which introduced by myself. For virtio-crypto stuff, I can
share the work with Michael (The whole virtio supporter).

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>