BRIEF-French watchdog says Dongfeng holds over 15 pct of PSA voting rights

May 4 (Reuters) - * French AMF market watchdog says China's Dongfeng holds 17.6 percent of voting rights in PSA Peugeot Citroen following attribution of double voting rights under the so-called Florange law, a move rewarding long-term investors. * The Chinese group, which became a PSA shareholder in 2014, held 110,622,220 PSA shares (13.68 percent of capital) and 180,488,886 voting right (17.16 percent of total) as of April 29. (Reporting by Paris Newsroom; paris.newsroom@thomsonreuters.com)