By Joseph Salvador The former Panthers star tweeted that he was joining the team’s coaching staff while wearing team apparel at their practice. Former wide receiver Steve Smith Sr. seemingly broke the news for himself that he landed his first NFL coaching job Thursday when he tweeted he was joining the Giants. But it was evidently a joke. “Guess what folks, I hate to break it to you, but it’s official,” Smith said while wearing Giants gear. “Agent 89 now is part of the coaching staff for the New York Giants. Sorry, just wanted to let you know. Breaking news myself, Rapsheet, Adam Schefter, you…