Clock module: fix compilation problem in ubuntu precise
Clock module: fix compilation problem in ubuntu precise

mejedi/tarantool,mejedi/tarantool,rtsisyk/tarantool,ocelot-inc/tarantool,rtsisyk/tarantool,rtsisyk/tarantool,mejedi/tarantool,ocelot-inc/tarantool,ocelot-inc/tarantool,rtsisyk/tarantool,ocelot-inc/tarantool,mejedi/tarantool