From my angle, the gesture was not intentional and the NHL seems to have been on the same page, as Subban was not reprimanded for the gesture.
Afterwards, Reaves didn't directly challenge the NHL's decision, but all signs point to him taking the law into his own hands. Just read between the lines. He's obviously holding a grudge! There is also the famous code between the players that is at stake.
Remember that Chris Kreider went after P.K. Subban in defense of his teammate, but the former Canadiens defenseman will likely have to pay for his action on Reaves when the Devils and Rangers meet. If I were number 76 for the Devils, I'd start boxing lessons now, because good old Ryan Reaves might want to dance with him.