amend! sequencer: remove unnecessary "or" in pick_one_commit()

sequencer: remove unnecessary "or" in pick_one_commit()

If error_with_patch(..., res, ...) succeeds then it returns "res", if
it fails then it returns -1. This means that or-ing the return value
with "res" is pointless as the result is the same as the return value.

Signed-off-by: Phillip Wood <phillip.wood@dunelm.org.uk>
Signed-off-by: Junio C Hamano <gitster@pobox.com>