In-order callbacks only work on simulated virtio user vdev.
* For Rx: If mergeable Rx buffers is enabled and in-order is enabled then
- ``virtio_xmit_pkts_inorder`` is used.
+ ``virtio_recv_mergeable_pkts_inorder`` is used.
* For Tx: If in-order is enabled then ``virtio_xmit_pkts_inorder`` is used.