Add cache locking functions in trylock variant

- Add cache trylock and read trylock functions.
- Introduce new error code -OCF_ERR_NO_LOCK.
- Change trylock functions in env to return this code in case of
  lock contention.

[ENV CHANGES REQUIRED]
Following functions should return 0 on success or -OCF_ERR_NO_LOCK
in case of lock contention:
- env_mutex_trylock()
- env_rwsem_up_read_trylock()
- env_rwsem_up_write_trylock()

Signed-off-by: Robert Baldyga <robert.baldyga@intel.com>

src/cleaning/cleaning.c

@@ -133,7 +133,7 @@ void ocf_cleaner_run(ocf_cleaner_t cleaner, ocf_queue_t queue)
 	}
 
 	/* Sleep in case there is management operation in progress. */
-	if (env_rwsem_down_write_trylock(&cache->lock) == 0) {
+	if (env_rwsem_down_write_trylock(&cache->lock)) {
 		cleaner->end(cleaner, SLEEP_TIME_MS);
 		return;
 	}