“Concussion” (2015) has the feel of a corporate espionage flick, what with all the liars in suits, suspicious suicides and a lonely hero raging against the machine. Except the machine is the NFL and we know how the story ends. Actually, the story hasn’t ended. For the next 40 years (think about that) retired athletes are going to be going mad and then dropping dead due to repeated blows to the head on the football field. Worse, for them, it’s already too late (think about that, too). It makes the film somewhat anticlimactic, despite a solid performance by Will Smith.