“Dune 2” launched in mainland China cinemas this weekend with a solid $19.9 million three-day haul. That put it in second place, narrowly behind holdover crime-drama “The Pig, the Snake and the Pigeon.” Data from consultancy firm Artisan Gateway, showed that “The Pig, the Snake and the Pigeon” earned $21.3 million (RMB151 million) between Friday …