Over his decades in entertainment, “ Scary Movie ” creator and star Marlon Wayans has confronted the same prejudices: Hollywood is convinced that international audiences won’t show up for comedies or films starring Black actors. “We’re trying to erase that old-school stigma,” says Wayans, who returned — along with several of his brothers — to the horror parody franchise after a 25-year absence. So when he was gearing up to promote “Scary Movie,” the sixth installment in the long-running series,