QNX: Fix EGL surface creation/destruction bugs. (#16310)

src/video/qnx/SDL_qnxgl.c

@@ -121,6 +121,7 @@ bool QNX_GLES_SwapWindow(SDL_VideoDevice *_this, SDL_Window *window)
             if (surface == EGL_NO_SURFACE) {
                 return false;
             }
+            SDL_SetPointerProperty(SDL_GetWindowProperties(window), SDL_PROP_WINDOW_QNX_SURFACE_POINTER, surface);
 
             if (!SDL_EGL_MakeCurrent(_this, surface, impl->context)) {
                 return false;

src/video/qnx/SDL_qnxvideo.c

@@ -547,6 +547,7 @@ static void QNX_DestroyWindow(SDL_VideoDevice *_this, SDL_Window *window)
     SDL_WindowData   *impl = (SDL_WindowData *)window->internal;
 
     if (impl) {
+        SDL_EGL_DestroySurface(_this, impl->egl_surface);
         screen_destroy_window(impl->window);
         window->internal = NULL;
     }