Buzz that MSNBC President Phil Griffin will soon be out at the Peacock Network is so strong that he’s even had to deny it to close friends, sources say. Griffin used to report to ex-NBC Universal chief Jeff Zucker, but since his departure, some say NBC President Steve Capus may show Griffin the door and take control of the cable news unit. “Capus wants the place to himself,” an industry insider said. “It’s a domino effect — Jeff Zucker . . . Keith Olbermann . . . next, Phil Griffin.” An MSNBC rep insisted, “The rumor you heard is totally false. There’s no truth to it.”