Included changes:
- properly release neigh_ifinfo in batadv_iv_ogm_process_per_outif()
- properly release orig_ifinfo->router when freeing orig_ifinfo
- properly release neigh_node objects during periodic check
- properly release neigh_info objects when the related hard_iface
is free'd
These changes are all very important because they fix some
reference counting imbalances that lead to the
impossibility of releasing the netdev object used by
batman-adv on shutdown.
The consequence is that such object cannot be destroyed by
the networking stack (the refcounter does not reach zero)
thus bringing the system in hanging state during a normal
reboot operation or a network reconfiguration.