Get the next -private from the lower neighbour list
void * netdev_lower_get_next_private(struct net_device * dev, struct list_head ** iter);
dev
device
iter
list_head ** of the current position
Gets the next netdev_adjacent->private from the dev's lower neighbour list, starting from iter position. The caller must hold either hold the RTNL lock or its own locking that guarantees that the neighbour lower list will remain unchainged.