Fix a regression with 'weird' dng fils missing MAKE/MODEL tags
Fix a regression with 'weird' dng fils missing MAKE/MODEL tags

There are DNG files (e.g. Blackmagic
URSA_1_1999-12-31_2153_C0003_000001.dng) that don't have the standard
MAKE/MODEL tiff tags, but might have a UNIQUECAMERAMODEL tag.

This fix restores the former behavior of falling back to that.

I believe there would be an even cleaner way to handle that by
incorporating the parsing of this fall-back string into the new TiffID
getID() function, but I know not enough about the different use cases
for all the canonical/make/model/id/... code. Someone else would need to
continue that.

Note: the Blackmagic files are still not supported with this fix, this
merely lets them fail where they were failing before ('unsupported
predictor'). See also https://github.com/klauspost/rawspeed/issues/104.

darktable-org/rawspeed,LebedevRI/rawspeed,LebedevRI/rawspeed,darktable-org/rawspeed,darktable-org/rawspeed,LebedevRI/rawspeed,LebedevRI/rawspeed,LebedevRI/rawspeed,darktable-org/rawspeed,darktable-org/rawspeed