The stillness of Arabia’s arid, inhospitable landscapes is disrupted when they become a battlefield for human conflict in “ Desert Warrior ,” the long-developing Saudi epic inspired by real ancient tribes and events that took place in the region. Strikingly photographed, if narratively run-of-the-mill, the latest from director Rupert Wyatt (“Rise of the Planet of the Apes”) begins 1,500 years ago when emperor Kisra II (Ben Kingsley in a one-scene appearance) orders his subjects to surrender