A power crowd came out to support David Geffen at a premiere of a new documentary on the mogul at the Paris Theatre last night. Geffen was spotted at the screening of PBS’ “Inventing David Geffen,” sitting with fellow DreamWorks co-founder Jeffrey Katzenberg and CBS chief Les Moonves. Calvin Klein recalled to us that he and Geffen were introduced by “Love Story” star Ali MacGraw in the 1970s. “David and I have been best friends for so many years,” he said. “We say things we wouldn’t say to anyone else. We met when I was doing [MacGraw’s] clothes for a film. He came with her . . . and, like that, we became best friends.” Graydon Carter, Barry Diller and Mike Nichols, who arrived with “Smash” star Anjelica Huston, hosted the Peggy Siegal Company screening and a VIP dinner at La Grenouille. Also spotted were Tom Freston, Regis Philbin, Andy Cohen and director Susan Lacy, who’s previously filmed “American Masters” docs on Paul Simon, Judy Garland and Leonard Bernstein.