Try to fix libcds counters issues

* For unknown reasons, _cdslib::_thread_counter is never initialized,
  trigger initialization manually by referencing during MemoryPool's
  construction.
* CircleCI linux.gcc test crashes on exit with an "invalid delete" at
  hpGC.reset() in libcds.cpp. I don't know what causes this, but it
  turns out we don't need garbage collection currently (we only use
  VyukovMPMCCycleQueue), so we can just remove the garbage collection
  for now.

include/libcds.h

@@ -17,5 +17,7 @@ namespace _cdslib
 	void thread_deinit();
 
 	static NiftyCounter<init, deinit> _counter;
-	static NiftyCounterTL<thread_init, thread_deinit> _thread_counter;
+	static thread_local NiftyCounterTL<_cdslib::thread_init, _cdslib::thread_deinit> _thread_counter;
 }
+
+#define CDS_THREAD_GUARD() (void)_cdslib::_thread_counter;