Prospective jurors were astonished yesterday to see Saul Berenson of “Homeland” report for duty. Mandy Patinkin, who plays the cerebral CIA division chief and mentor to Claire Danes’ character, Carrie Mathison, on the Showtime series, showed up at the Centre Street courthouse. We’re told, “He was questioned as part of the group for a trial. But it was a little awkward because the lawyers asked him very personal questions, like where he lived, what he did for a living. He said he was an actor but didn’t say what show, but in the middle of the potential jurors being questioned, the judge said he was a ‘big fan.’ ” Patinkin didn’t get picked, which was probably a relief to every defendant coming up for trial.