It took a second for John Henry to decipher the loud chant ringing through Fenway Park. “Oh, sell the team,” Henry said to someone off screen before slyly smiling during the Red Sox’s loss to the Brewers on April 6 that dropped Boston to 2-8. Those chants have become more and more prevalent in recent years with the Red Sox failing to uphold their championship standards and fans accusing Henry of being aloof. John Henry is not beloved in Boston these days. AP The remarks don’t fluster the 76-year-old founder of sports holding conglomerate Fenway Sports Group, especially compared to what he’s experienced in his other duties as Liverpool’s owner. “Fans get frustrated,” Henry told the Sports Business Journal in a recent profile . “The Sox looked terrible for (their) first 25 games. I remember a plane flying overhead when we (Liverpool) were beating Manchester United 7-0 that read ‘FSG OUT!’” “It doesn’t mean you ignore them, it means you work harder— you don’t settle for mediocrity.…