emulator: opengl: add missing EGLDisplay destructor

Change-Id: I788904a597b7929a7fc7a5db3cf5baa79b9f1936
diff --git a/tools/emulator/opengl/system/egl/eglDisplay.cpp b/tools/emulator/opengl/system/egl/eglDisplay.cpp
index 881b8d6..7beeb8e 100644
--- a/tools/emulator/opengl/system/egl/eglDisplay.cpp
+++ b/tools/emulator/opengl/system/egl/eglDisplay.cpp
@@ -70,6 +70,11 @@
     pthread_mutex_init(&m_lock, NULL);
 }
 
+eglDisplay::~eglDisplay()
+{
+    pthread_mutex_destroy(&m_lock);
+}
+
 bool eglDisplay::initialize(EGLClient_eglInterface *eglIface)
 {
     pthread_mutex_lock(&m_lock);
diff --git a/tools/emulator/opengl/system/egl/eglDisplay.h b/tools/emulator/opengl/system/egl/eglDisplay.h
index 934c699..9d979d9 100644
--- a/tools/emulator/opengl/system/egl/eglDisplay.h
+++ b/tools/emulator/opengl/system/egl/eglDisplay.h
@@ -33,6 +33,7 @@
 {
 public:
     eglDisplay();
+    ~eglDisplay();
 
     bool initialize(EGLClient_eglInterface *eglIface);
     void terminate();