The CNN weekly prime time talk show co-hosted by basketball loudmouth Charles Barkley and CBS morning star Gayle King has ended a six-month run that failed to produce ratings. The weekly call-in show “King Charles,” which aired at 10 p.m. Eastern time on Wednesday nights failed to generate more viewers than reruns of the sitcom “Friends” and episodes of “South Park.” It was the lowest-rated prime time weeknight series debut for CNN in at least a decade, according to Nielsen.