This fix icludes workaround for Irix compiler bug & removs some unused
variables (resulted in warnings)


server-tools/instance-manager/mysql_connection.cc:
  removed unused variable
server-tools/instance-manager/parse.cc:
  removed unused variable
server-tools/instance-manager/thread_registry.cc:
  Workaround for the Irix compiler bug
server-tools/instance-manager/user_map.cc:
  removed unused variable