Fixed new introduced bug in my_time.c


BitKeeper/deleted/.del-valgrind.supp.orig:
  Delete: mysql-test/valgrind.supp.orig
mysys/my_thr_init.c:
  More comments
  Don't abort if we call my_thread_end() multiple times
sql-common/my_time.c:
  Fixed wrong patch in last commit
sql/sql_cache.cc:
  Fixed old bad merge (not critical)
sql/tztime.cc:
  Portability fix