iproute2: sch_rr support in tc

iproute2: sch_rr support in tc

This patch applies on top of Patrick McHardy's RTNETLINK
patches to add nested compat attributes.  This is needed to maintain
ABI for sch_{rr|prio} in the kernel with respect to tc.  A new option,
namely multiqueue, was added to sch_prio and sch_rr.  This will allow
a user to turn multiqueue support on for sch_prio or sch_rr at loadtime.
Also, tc qdisc ls will display whether or not multiqueue is enabled on
that qdisc.  When in multiqueue mode, a user can specify a value of 0 for
bands, and the number of bands will be created to match the number of
queues on the device.

This patch is to support the new sch_rr (round-robin) qdisc being proposed
in NET for multiqueue network device support in the Linux network stack.
It uses q_prio.c as the template, since the qdiscs are nearly identical,
outside of the ->dequeue() routine.

Signed-off-by: Peter P Waskiewicz Jr <peter.p.waskiewicz.jr@intel.com>