Three men who contend they were wrongly convicted of a double murder and armed robbery 20 years ago will get new trials after the Cook County state’s attorney’s office asked a judge to vacate their convictions Monday.When Charles Johnson and Larod Styles were teenagers, they received life sentences for the 1995 murders of Yousef Ali and Khaled Ibrahim, the owners of a South Side used car lot. They were also convicted of attempting to murder two employees of Elegant Auto as well as armed robbery.A third teenager …