Billionaire Carlos Slim will buy out AT&T’s stake in America Movil SAB for $5.57 billion, propping up his Latin American mobile-phone company’s stock price. AT&T is selling its holdings of Slim’s company to avoid a conflict of interest because the company is buying DirecTV, which competes with America Movil for pay-TV customers across Latin America. AT&T expects to report a gain of 8 cents to 10 cents a share from the sale.