Ensure DUCK code works properly with DAG 3.X drivers

[spa1]

I've updated and tested format_dag_25 for regular DAG capture using the DAG 3 series of drivers, but I haven't taken the time to ensure recording DUCK information still works correctly with the newer software. We should definitely do this at some stage, but it remains low priority for now because, as far as I am aware, we're the only ones that use DUCK and we won't be using DAG 3 drivers on that capture point any time soon.