emulator: opengl: add missing pthread_mutex_destroy

Change-Id: Ib6be00619e06f5ff492a080d1feb2954b626fa26
diff --git a/tools/emulator/opengl/shared/OpenglOsUtils/osThreadUnix.cpp b/tools/emulator/opengl/shared/OpenglOsUtils/osThreadUnix.cpp
index 0cddb64..66611ee 100644
--- a/tools/emulator/opengl/shared/OpenglOsUtils/osThreadUnix.cpp
+++ b/tools/emulator/opengl/shared/OpenglOsUtils/osThreadUnix.cpp
@@ -27,6 +27,7 @@
 
 Thread::~Thread()
 {
+    pthread_mutex_destroy(&m_lock);
 }
 
 bool