The reusable fairness queueing implementation (fq.h) lacks the memory
usage limit that the fq_codel qdisc has. This means that small
devices (e.g. WiFi routers) can run out of memory when flooded with a
large number of packets. This ports the memory limit feature from
fq_codel to fq.h.
Signed-off-by: NToke Høiland-Jørgensen <toke@toke.dk>
Signed-off-by: NJohannes Berg <johannes.berg@intel.com>