Fixed tests for RAID tables
Detect uninitialized mutexes on lock and destroy


mysql-test/r/raid.result:
  Updated results
mysql-test/r/rpl_change_master.result:
  Update results missing from last patch
mysql-test/t/raid.test:
  Clean up test
mysys/mf_iocache.c:
  Comments
  Small safety fix
mysys/thr_mutex.c:
  Detect uninitialized mutexes on lock and destroy
sql/sql_db.cc:
  Fixed memory leak with RAID tables