Fix BUG in do_test_for_insn_bits() while testing irrelevant subdevices that are busy.
Fix BUG in do_test_for_insn_bits() while testing irrelevant subdevices
that are busy.

Linux-Comedi/comedilib,Linux-Comedi/comedilib,olsonse/comedilib,olsonse/comedilib,Linux-Comedi/comedilib,olsonse/comedilib,olsonse/comedilib,Linux-Comedi/comedilib,Linux-Comedi/comedilib,olsonse/comedilib,olsonse/comedilib,Linux-Comedi/comedilib