cryptodev: wrap the ready flag

The ready flag should be set by the children of
cryptodev backend interface. Warp the setter/getter
functions for it.

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>
diff --git a/hw/virtio/virtio-crypto.c b/hw/virtio/virtio-crypto.c
index 6318fcf..9213258 100644
--- a/hw/virtio/virtio-crypto.c
+++ b/hw/virtio/virtio-crypto.c
@@ -732,7 +732,7 @@
     VirtIOCrypto *vcrypto = VIRTIO_CRYPTO(vdev);
     /* multiqueue is disabled by default */
     vcrypto->curr_queues = 1;
-    if (!vcrypto->cryptodev->ready) {
+    if (!cryptodev_backend_is_ready(vcrypto->cryptodev)) {
         vcrypto->status &= ~VIRTIO_CRYPTO_S_HW_READY;
     } else {
         vcrypto->status |= VIRTIO_CRYPTO_S_HW_READY;
@@ -792,7 +792,7 @@
     }
 
     vcrypto->ctrl_vq = virtio_add_queue(vdev, 64, virtio_crypto_handle_ctrl);
-    if (!vcrypto->cryptodev->ready) {
+    if (!cryptodev_backend_is_ready(vcrypto->cryptodev)) {
         vcrypto->status &= ~VIRTIO_CRYPTO_S_HW_READY;
     } else {
         vcrypto->status |= VIRTIO_CRYPTO_S_HW_READY;