CHICAGO — After being held for more than a year in Brooklyn, Chicago-born R&B star R. Kelly was back at the federal jail in the Loop on Wednesday in advance of his second criminal trial set for next month. Records show Kelly, 55, was moved Tuesday from Brooklyn to the Metropolitan Correctional Center on West Van Buren Street, where he first landed more than three years ago after his arrest on separate federal indictments filed in Chicago and New York. Just two weeks ago, Kelly was sentenced to a 30-year prison term for his racketeering conviction in U.S. District Court in Brooklyn. He’s appeal…