nfp: flower: ignore duplicate cb requests for same rule

If a flower rule has a repr both as ingress and egress port then 2
callbacks may be generated for the same rule request.

Add an indicator to each flow as to whether or not it was added from an
ingress registered cb. If so then ignore add/del/stat requests to it from
an egress cb.

Signed-off-by: John Hurley <john.hurley@netronome.com>
Reviewed-by: Jakub Kicinski <jakub.kicinski@netronome.com>
Signed-off-by: David S. Miller <davem@davemloft.net>