SCUBA2: remove stray debugging code
SCUBA2: ensure the subarray is set in the uhdr

If the QA assessment fails because the subarray has no bolometers,
then the SUBARRAY entry to be stored in the index file is undef. Set
it in the uhdr to ensure it is always present.
SCUBA2: set the product to NOISE

Setting a tag isn't always enough.

Also clarify the use of the initial results hash by renaming it to
avoid duplicate names (%results was used twice).