nfp: flower: add get_flow_act_ct() for ct action

CT action is a special case different from other actions, CT clear action
is not required when get ct action, but this case is not considered.
If CT clear action in the flow rule, skip the CT clear action when get ct
action, return the first ct action that is not a CT clear action

Signed-off-by: Wentao Jia <wentao.jia@corigine.com>
Acked-by: Simon Horman <simon.horman@corigine.com>
Signed-off-by: Louis Peens <louis.peens@corigine.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>