Travis Kelce is being lined up for a guest star appearance on ‘Law and Order: SVU’. The 35-year-old NFL’s star’s girlfriend is a huge fan of the long-running series, even naming one of her cat’s Olivia after the main character Detective Olivia Benson, and star Mariska Hargitay has hinted that Travis could soon appear on the show. She told Entertainment Tonight: “I heard through the grapevine that he is a fan of the show. I think both brothers are.” Mariska admitted that she has received a number of ideas on how Travis could be incorporated into the show. Travis and his retired NFL player broth…