LOS ANGELES — In the days leading to the Rose Bowl, Michigan quarterback J.J. McCarthy admitted that a year ago, he was caught up in what he described as the noise and the emotions of playing in a national semifinal playoff game, his first as the starter. It wasn’t the performance he had hoped to produce, throwing two pick-sixes in the loss to TCU that stalled the Wolverines’ plans for a national championship. Fast-forward to now, and McCarthy said he’s been keeping it simple in the lead-up to No. 1 Michigan’s third consecutive College Football Playoff national semifinal, this time against No….