A deflating second half Saturday night in College Station, Texas, shouldn’t necessarily sink LSU’s potential College Football Playoff hopes. But coach Brian Kelly said his Tigers (6-2, 3-1) have clear issues to address with now a thin line to walk toward those postseason goals following their 38-23 loss to No. 14 Texas A&M (7-1, 5-0). “I mean, we’ve lost our margin, right?” he said after the game. “We have no margin for error. We have to go back and look at some of the things I just talked about, right? We have to build balance within the offense. We have to be able to handle the running quart…