Delete deprecated Hacking in tox.ini
Delete deprecated Hacking in tox.ini

Some hacking have been removed,so we can delete them.
More details:
    https://github.com/openstack-dev/hacking/blob/master/setup.cfg

Change-Id: I1da4cae962987d8174384daadd5eb2cf4ff746c4

openstack/dragonflow,openstack/dragonflow,openstack/dragonflow