Implement exclusive monitor

src/core/arm/exclusive_monitor.cpp

@@ -0,0 +1,7 @@
+// Copyright 2018 yuzu emulator team
+// Licensed under GPLv2 or any later version
+// Refer to the license.txt file included.
+
+#include "core/arm/exclusive_monitor.h"
+
+ExclusiveMonitor::~ExclusiveMonitor() = default;