MFC 301516,301520,301531,301535,301540,301542,301628: Traffic scheduling

MFC 301516,301520,301531,301535,301540,301542,301628: Traffic scheduling
updates.

301516:
cxgbetool: Allow max-rate > 10Gbps for rate-limited traffic.

301520:
cxgbe(4): Create a reusable struct type for scheduling class parameters.

301531:
cxgbe(4): Break up set_sched_class.  Validate the channel number and
min/max rates against their actual limits (which are chip and port
specific) instead of hardcoded constants.

301535:
cxgbe(4): Track the state of the hardware traffic schedulers in the
driver.  This works as long as everyone uses set_sched_class_params
to program them.

301540:
cxgbe(4): Provide information about traffic classes in the sysctl mib.

301542:
cxgbe(4): A couple of fixes to set_sched_queue.

- Validate the scheduling class against the actual limit (which is chip
  specific) instead of a magic number.

- Return an error if an attempt is made to manipulate the tx queues of a
  VI that hasn't been initialized.

301628:
cxgbe(4): Add a sysctl to manage the binding of a txq to a traffic class.

Sponsored by:	Chelsio Communications

git-svn-id: svn://svn.freebsd.org/base/stable/10@308321 ccf9f872-aa2e-dd11-9fc8-001c23d0bc1f