ATLANTA — Michael Vick made a triumphant return to the Georgia Dome on Sunday, riding onto the field in a convertible to a raucous ovation that made it clear Atlanta Falcons have forgiven their former franchise quarterback. Despite an online campaign calling for the Falcons to revoke their invitation over a dogfighting case that sent Vick to prison for nearly two years, he received by far the loudest ovation from the sellout crowd of 70,835 during a ceremony honoring the final regular-season game at the team’s home of 25 years. “There are a lot of people who forgave me,” Vick said before the game.