tray: linux fix tray menu elements not running callbacks (#13626)

src/core/unix/SDL_gtk.c

@@ -223,5 +223,6 @@ void SDL_UpdateGtk(void)
 {
     if (IsGtkInit()) {
         gtk.g.main_context_iteration(sdl_main_context, GTK_FALSE);
+        gtk.g.main_context_iteration(NULL, GTK_FALSE);
     }
 }

src/tray/unix/SDL_tray.c

@@ -166,7 +166,7 @@ struct SDL_Tray {
     GtkMenuShell *menu_cached;
 };
 
-static void call_callback(GtkMenuItem *item, GParamSpec *pspec, gpointer ptr)
+static void call_callback(GtkMenuItem *item, gpointer ptr)
 {
     SDL_TrayEntry *entry = ptr;