Reese Witherspoon and Deacon Phillippe Rodin Eckenroth/Getty Images Reese Witherspoon had the perfect date for the premiere of her pal Zoë Kravitz’s new movie. The actress and producer, 48, was joined by her son Deacon Phillippe — whom she shares with actor Ryan Phillippe — as she supported Kravitz at the Los Angeles premiere of…