This patch fixed below issues in the packed ring based control
vq support in virtio user:
1. The idx_hdr should be used_idx instead of the id in the desc;
2. We just need to write out a single used descriptor for each
descriptor list;
3. The avail/used bits should be initialized to 0;
Meanwhile, make the function name consistent with other parts.
Fixes: 48a4464029a7 ("net/virtio-user: support control VQ for packed")
Signed-off-by: Tiwei Bie <tiwei.bie@intel.com>
Reviewed-by: Maxime Coquelin <maxime.coquelin@redhat.com>
45c224e73a