General: address feedback

src/video_core/gpu.cpp

@@ -355,7 +355,7 @@ struct GPU::Impl {
 
     std::condition_variable sync_cv;
 
-    std::list<std::function<void(void)>> sync_requests;
+    std::list<std::function<void()>> sync_requests;
     std::atomic<u64> current_sync_fence{};
     u64 last_sync_fence{};
     std::mutex sync_request_mutex;