net/sched: act_pedit, setup offload action for action stats query

A single tc pedit action may be translated to multiple flow_offload
actions.
Offload only actions that translate to a single pedit command value.

Signed-off-by: Oz Shlomo <ozsh@nvidia.com>
Reviewed-by: Simon Horman <simon.horman@corigine.com>
Reviewed-by: Marcelo Ricardo Leitner <marcelo.leitner@gmail.com>
Acked-by: Jamal Hadi Salim <jhs@mojatatu.com>
Signed-off-by: Paolo Abeni <pabeni@redhat.com>