HIVE-7705 : there's a useless threadlocal in LBUtils that shows up in perf profiles (Sergey Shelukhin, Navis reviewed by Gopal V, Navis)

git-svn-id: https://svn.apache.org/repos/asf/hive/trunk@1618671 13f79535-47bb-0310-9956-ffa450edef68