Merge branch 'reusable-codel'

Michal Kazior says:

====================
codel: make it reuseable beyond qdiscs

There's an ongoing effort in fixing wireless
bufferbloat. As part of that fq_codel is being
ported into mac80211. To prevent code duplication
codel.h needs to be slightly modified before it
can be used in mac80211 (or other drivers FWIW).

For more background please see:

  https://www.spinics.net/lists/linux-wireless/msg149976.html
====================

Signed-off-by: David S. Miller <davem@davemloft.net>