Bruce Davison already owns a chunk of pop culture—he was devious in the first two X-Men movies and has appeared in episodes of everything from “Lost” and “Battlestar Galactica” to “Terminator” and “The L Word.” So it can’t be too much of a surprise that when the producers of new “Knight Rider” series wanted a genre veteran to lend credibility to the show, they, too, turned to Davison.