CHICAGO — The Chicago Bulls returned to the United Center for their first playoff game in five years with home-court advantage and the momentum of a road win at their back. But they limped out of Game 3 with a 111-81 beatdown as the Milwaukee Bucks bounced back like a reigning NBA champion to take a 2-1 lead in the first-round series. Bulls fans poured into the United Center with frenetic excitement, drowning out the team’s introduction videos. But that enthusiasm dulled in the first quarter of the blowout. By the time Patrick Williams threw away a turnover in the third quarter, scattered boos…