Merge branch 'dd/bisect-helper-subcommand'

Fix a regression in the bisect-helper which mistakenly treats
arguments to the command given to 'git bisect run' as arguments to
the helper.

* dd/bisect-helper-subcommand:
  bisect--helper: parse subcommand with OPT_SUBCOMMAND
  bisect--helper: move all subcommands into their own functions
  bisect--helper: remove unused options

diff --cc builtin/bisect--helper.c
Simple merge