MANY legitimate actors who appeared in “Caligula” disowned it after producer Bob Guccione turned the 1979 historical epic into a sleazy porn flick by adding hardcore lesbian scenes with Penthouse Pets. But time heals. A DVD reissue will feature commentaries by Malcolm McDowell, who played the title role, and Helen Mirren. Conspicuously absent are Peter O’Toole and Gore Vidal, who wrote the first script, then distanced himself from the project.