ice: enable ndo_setup_tc support for mqprio_qdisc

Add support in driver for TC_QDISC_SETUP_MQPRIO. This support
enables instantiation of channels in HW using existing MQPRIO
infrastructure which is extended to be offloadable. This
provides a mechanism to configure dedicated set of queues for
each TC.

Configuring channels using "tc mqprio":
--------------------------------------
tc qdisc add dev <ethX> root mqprio num_tc 3 map 0 1 2 \
	queues 4@0 4@4 4@8  hw 1 mode channel

Above command configures 3 TCs having 4 queues each. "hw 1 mode channel"
implies offload of channel configuration to HW. When driver processes
configuration received via "ndo_setup_tc: QDISC_SETUP_MQPRIO", each
TC maps to HW VSI with specified queues.

User can optionally specify bandwidth min and max rate limit per TC
(see example below). If shaper params like min and/or max bandwidth
rate limit are specified, driver configures VSI specific rate limiter
in HW.

Configuring channels and bandwidth shaper parameters using "tc mqprio":
----------------------------------------------------------------
tc qdisc add dev <ethX> root mqprio \
	num_tc 4 map 0 1 2 3 queues 4@0 4@4 4@8 4@12 hw 1 mode channel \
	shaper bw_rlimit min_rate 1Gbit 2Gbit 3Gbit 4Gbit \
	max_rate 4Gbit 5Gbit 6Gbit 7Gbit

Command to view configured TCs:
-----------------------------
tc qdisc show dev <ethX>

Deleting TCs:
------------
tc qdisc del dev <ethX> root mqprio

Signed-off-by: Kiran Patil <kiran.patil@intel.com>
Signed-off-by: Amritha Nambiar <amritha.nambiar@intel.com>
Signed-off-by: Sudheer Mogilappagari <sudheer.mogilappagari@intel.com>
Tested-by: Bharathi Sreenivas <bharathi.sreenivas@intel.com>
Signed-off-by: Tony Nguyen <anthony.l.nguyen@intel.com>