It’s mind over mayhem, as Warner Bros. Pictures has just unveiled the teaser poster for its upcoming action adventure “Birds of Prey (And the Fantabulous Emancipation of One Harley Quinn).” Directed by Cathy Yan (“Dead Pigs”), “Birds of Prey” follows Harley Quinn (Margot Robbie) as she joins forces with Black Canary (Jurnee Smollett-Bell), the Huntress…