vdpa/mlx5: Update Control VQ callback information

The control VQ specific information is stored in the dedicated struct
mlx5_control_vq. When the callback is updated through
mlx5_vdpa_set_vq_cb(), make sure to update the control VQ struct.

Fixes: 5262912e ("vdpa/mlx5: Add support for control VQ and MAC setting")
Signed-off-by: Eli Cohen <elic@nvidia.com>
Message-Id: <20220613075958.511064-1-elic@nvidia.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Acked-by: Jason Wang <jasowang@redhat.com)

drivers/vdpa/mlx5/net/mlx5_vnet.c

@@ -1962,6 +1962,8 @@ static void mlx5_vdpa_set_vq_cb(struct vdpa_device *vdev, u16 idx, struct vdpa_c
 	struct mlx5_vdpa_net *ndev = to_mlx5_vdpa_ndev(mvdev);
 
 	ndev->event_cbs[idx] = *cb;
+	if (is_ctrl_vq_idx(mvdev, idx))
+		mvdev->cvq.event_cb = *cb;
 }
 
 static void mlx5_cvq_notify(struct vringh *vring)