Revert "abdi_processargs: use intermediate 'args' class"

This reverts commit d5d80829dd64b1827351280a08062692e172f326.
Arcyd: refactor, move repo args to new module

Test Plan:
$ ./precommit.sh
Arcyd: refactor, inline setup_parser

The split of which args are in abdi_processargs vs. abdcmd_processrepos
seems arbitrary, consoliate them in abdcmd_processrepos.

Test Plan:
$ ./precommit.sh
$ git grep abdi_processargs.setup_parser