CHILDISH staffers at the "Today" show have been reduced to homophobic name-calling about their rivals at "Good Morning America" - Diane Sawyer, Chris Cuomo, Robin Roberts and Sam Champion. A network source says, " 'Today' staffers, from top to bottom, executives to interns, refer to 'GMA' as 'Gay-MA' " and snicker about the hosts. "GMA" has been gaining in the ratings on No. 1 "Today" and cut its lead in half. For their part, the "GMA" folks are said to refer to "Today" as "Yesterday." Reps for both shows declined to comment.