By Joseph White and Joshua Schneyer DETROIT (Reuters) – Hyundai Motor Co, Korea’s top automaker, is investigating child labor violations in its U.S. supply chain and plans to “sever ties” with Hyundai suppliers in Alabama found to have relied on underage workers, the company’s global chief operating officer Jose Munoz told Reuters on Wednesday. A Reuters investigative report in July documented children, including a 12-year-old, working at a Hyundai-controlled metal stamping plant in rural Luverne, Alabama, called SMART Alabama, LLC. Following the Reuters report, Alabama’s state Department of L…