nfp: flower: support to offload pedit of IPv6 flowinto fields

Previously the traffic class field is ignored while firmware has
already supported to pedit flowinfo fields, including traffic
class and flow label, now add it back.

Signed-off-by: Yinjun Zhang <yinjun.zhang@corigine.com>
Link: https://lore.kernel.org/r/20220609080136.151830-1-simon.horman@corigine.com


Signed-off-by: Jakub Kicinski <kuba@kernel.org>