common/iavf: support ETS-based QoS offload configuration

common/iavf: support ETS-based QoS offload configuration

This patch adds new virtchnl opcodes and structures for QoS
configuration, which includes:
1. VIRTCHNL_VF_OFFLOAD_TC, to negotiate the capability supporting QoS
configuration. If VF and PF both have this flag, then the ETS-based QoS
offload function is supported.
2. VIRTCHNL_OP_DCF_CONFIG_BW, DCF is supposed to configure min and max
bandwidth for each VF per enabled TCs. To make the VSI node bandwidth
configuration work, DCF also needs to configure TC node bandwidth
directly.
3. VIRTCHNL_OP_GET_QOS_CAPS, VF queries current QoS configuration, such
as enabled TCs, arbiter type, up2tc and bandwidth of VSI node. The
configuration is previously set by DCB and DCF, and now is the potential
QoS capability of VF. VF can take it as reference to configure queue TC
mapping.
4. VIRTCHNL_OP_CONFIG_TC_MAP, set VF queues to TC mapping for all Tx and
Rx queues. Queues mapping to one TC should be continuous and all
allocated queues should be mapped.

Signed-off-by: Ting Xu <ting.xu@intel.com>
Acked-by: Qi Zhang <qi.z.zhang@intel.com>