common/iavf: support flow director in virtual channel

common/iavf: support flow director in virtual channel

Adds new ops and structures to support VF to add/delete/validate/
query flow director.

ADD and VALIDATE FDIR share one ops: VIRTCHNL_OP_ADD_FDIR_FILTER.
VF sends this request to PF by filling out the related field in
virtchnl_fdir_add. If the rule is created successfully, PF
will return flow id and program status to VF. If the rule is
validated successfully, the PF will only return program status
to VF.

DELETE FDIR uses ops: VIRTCHNL_OP_DEL_FDIR_FILTER.
VF sends this request to PF by filling out the related field in
virtchnl_fdir_del. If the rule is deleted successfully, PF
will return program status to VF.

Query FDIR uses ops: VIRTCHNL_OP_QUERY_FDIR_FILTER.
VF sends this request to PF by filling out the related field in
virtchnl_fdir_query. If the request is successfully done by PF,
PF will return program status and query info to VF.

Signed-off-by: Simei Su <simei.su@intel.com>
Signed-off-by: Paul M Stillwell Jr <paul.m.stillwell.jr@intel.com>
Signed-off-by: Qi Zhang <qi.z.zhang@intel.com>
Acked-by: Beilei Xing <beilei.xing@intel.com>