remove unused List

sql/ha_ndbcluster.cc

@@ -8413,7 +8413,6 @@ pthread_handler_t ndb_util_thread_func(void *arg __attribute__((unused)))
 {
   THD *thd; /* needs to be first for thread_stack */
   struct timespec abstime;
-  List<NDB_SHARE> util_open_tables;
   Thd_ndb *thd_ndb;
   uint share_list_size= 0;
   NDB_SHARE **share_list= NULL;