selftests: ublk: use auto_zc for PER_IO_DAEMON tests in stress_04
stress_04 is described as "run IO and kill ublk server(zero copy)" but
the --per_io_tasks tests cases don't use zero copy. Plus, one of the
test cases is duplicated. Add --auto_zc to these test cases and
--auto_zc_fallback to one of the duplicated ones. This matches the test
cases in stress_03.
Signed-off-by: Caleb Sander Mateos <csander@purestorage.com> Reviewed-by: Ming Lei <ming.lei@redhat.com> Signed-off-by: Jens Axboe <axboe@kernel.dk>