Same thing as for AGIPD.  Proposing to save this alongside the module mapping (if we're creating
YAML files per module anyway).  Note that I had to add "cap" and "qm" layers to old_const and
old_mdata; there's probably only one element in each, so the dictionary is overkill, but as we loop
over both, this would otherwise break if we ever have more than one of either...