SANTA CLARA, Calif. — This Nick Bosa speech cannot wait until the eve of Super Bowl XLVIII. Instead, the star defensive end has a message to share. “You don’t understand it as much as a rookie, how hard it is to get there, how hard you have play, how locked in you have to be for the entire four quarters if you actually want to win. I’ve learned that,” Bosa said. He and the 49ers learned the hard way four years ago, when they couldn’t hold a 10-point lead with seven minutes remaining in their 31-20, Super Bowl loss to the Chiefs. “I’m just going to relay to the guys there has to be a different …