HONG KONG — If there’s one lingering sore point between Hollywood and China, it’s Tibet. For years, celebrity activists have annoyed Beijing by organizing charity concerts for Tibetan independence, shouting “Free Tibet” at awards ceremonies, and palling around with the Dalai Lama. You would think the idea of a major studio collaborating with the Chinese government on a Tibet movie would not only be radioactive, but also absurd. But such is the dependence of Hollywood on China now that the absurd has become real.