[client] egl: fix building without EGL support

client/src/app.c

@@ -566,6 +566,7 @@ bool app_getProp(LG_DSProperty prop, void * ret)
   return g_state.ds->getProp(prop, ret);
 }
 
+#ifdef ENABLE_EGL
 EGLDisplay app_getEGLDisplay(void)
 {
   return g_state.ds->getEGLDisplay();
@@ -580,6 +581,7 @@ void app_eglSwapBuffers(EGLDisplay display, EGLSurface surface)
 {
   g_state.ds->eglSwapBuffers(display, surface);
 }
+#endif
 
 void app_glSwapBuffers(void)
 {