Remove mutex

Author: PietroGhg

source/adapters/native_cpu/common.hpp

@@ -11,7 +11,6 @@
 #pragma once
 
 #include "ur/ur.hpp"
-#include <mutex>
 
 constexpr size_t MaxMessageSize = 256;
 
@@ -64,7 +63,6 @@ struct _ur_object {
 
 struct RefCounted {
   std::atomic_uint32_t _refCount;
-  std::mutex _mutex;
   void incrementReferenceCount() { _refCount++; }
   void decrementReferenceCount() { _refCount--; }
   RefCounted() : _refCount{1} {}
@@ -74,7 +72,6 @@ struct RefCounted {
 template <typename T>
 inline void decrementOrDelete(T* refC) {
   refC->decrementReferenceCount();
-  std::lock_guard<std::mutex> lock(refC->_mutex);
   if (refC->getReferenceCount() == 0)
     delete refC;
 }