Wynn Resorts Ltd. is seeking to block Elaine Wynn-a major shareholder, longtime director and the ex-wife of company Chairman Steve Wynn-from its board, in the latest tussle at the casino operator with resorts in Las Vegas and Macau. The board decided not to renominate Wynn, who has served for more than a dozen years, once her term expires at the company’s next annual meeting April 24, according to a Friday filing by the company.