It’s difficult to watch “Jodorowsky’s Dune” and not come to the conclusion that, on balance, it’s probably a good thing that motion picture adaptation of Frank Herbert’s ‘Dune’ didn’t actually get made. Had it been made, it would have no doubt been a psychedelic, surrealist masterwork; a curate’s egg of titanic proportions which would have bestrode cinema and sci-fi for generations but at a…