It's been knocking around for more than a decade, but the revival of Rodgers and Hart classic ''Pal Joey,'' with a book adapted by Richard Greenberg from John O'Hara's original, appears set for a Broadway stage; it even has an opening date and a theater. The Roundabout Theater Company will produce ''Pal Joey'' in association with Marc Platt, the last commercial producer to have his hands on it, at Studio 54. Previews are to begin on Nov. 21 with an official opening scheduled for Dec. 11. Choreography will be by Graciela Daniele and musical direction by Paul Gemignani;Joe Mantello will direct. The cast has not been announced. [ABSTRACT FROM PUBLISHER]