bootanimation: Call eglReleaseThread in threadLoop

Add eglReleaseThread call in the threadLoop function to
ensure that the thread properly cleans up its resources
before exiting.

Change-Id: I90dff47370e7acaecc046c43f0bb274214a29f77

cmds/bootanimation/BootAnimation.cpp

@@ -322,6 +322,7 @@ bool BootAnimation::threadLoop()
     mFlingerSurface.clear();
     mFlingerSurfaceControl.clear();
     eglTerminate(mDisplay);
+    eglReleaseThread();
     IPCThreadState::self()->stopProcess();
     return r;
 }