Afficianados know that Whoopi Goldberg’s parents didn’t name her Whoopi and their last name wasn’t Goldberg. In fact, she was born Caryn Elaine Johnson, and only took her stage name after someone made a petty joke about flatulence. Her double identity proved a very useful disguise when the bawdy comedienne’s Soho loft sold: City records showed this morning that Caryn Johnson–Ms. Goldberg, that is–sold her two-bedroom apartment at 101 Wooster Street to…