CTL: Allow userland supply tags via ioctl frontend.
Before this ioctl frontend always replaced tags with sequential ones.
It was done for ctladm, that can not keep track of global tag list.
But in case of virtio-scsi in bhyve we can pass provided tags as-is.
It should be on virtio-scsi initiator to provide us valid tags. It
should allow proper task management, error reporting, etc. In case
of several virtio-scsi devices, they should use different CTL ports
or initiator IDs to avoid conflicts, but this is expected by design.
PR: 267539