HOUSTON — Entering Wednesday, Kevin McHale had accumulated the best winning percentage of any coach in Rockets franchise history and was mere months removed from somehow guiding his injury-plagued team to an unexpected berth in the Western Conference finals. Before lunch, he was fired. Because of 11 regular-season games. McHale, who was in his fifth season as Houston’s coach, was let go just 11 games into his new three-year, $12 million contract extension. In other words, expectations are high enough that owner