King Size Law Suit? Tri-Villa Trust of Boston filed a lawsuit yesterday in federal court in Boston claiming both CNN and Universal Studios used without permission photographs of Elvis and Priscilla Presley that belong to the trust. The suit alleges CNN violated Tri-Villa's copyright and misused the two photographs, both taken in Palm Springs, Calif., by showing them on ''Larry King Live'' during an interview of Joe Esposito, who is billed as Elvis's confidant, about his relationship with the King. And Universal used the photos - one of the couple locking arms and drinking juice and the other with Priscilla on Elvis's lap - in a DVD without permission. The amount of damages sought was not specified.