Remove duplicate config

src/video_core/shader/async_shaders.cpp

@@ -36,6 +36,7 @@ void AsyncShaders::AllocateWorkers(std::size_t num_workers) {
 void AsyncShaders::FreeWorkers() {
     // Mark all threads to quit
     is_thread_exiting.store(true);
+    cv.notify_all();
     for (auto& thread : worker_threads) {
         thread.join();
     }

src/yuzu/configuration/config.cpp

@@ -1149,8 +1149,6 @@ void Config::SaveRendererValues() {
                        Settings::values.use_assembly_shaders, false);
     WriteSettingGlobal(QStringLiteral("use_asynchronous_shaders"),
                        Settings::values.use_asynchronous_shaders, false);
-    WriteSettingGlobal(QStringLiteral("use_asynchronous_shaders"),
-                       Settings::values.use_asynchronous_shaders, false);
     WriteSettingGlobal(QStringLiteral("use_fast_gpu_time"), Settings::values.use_fast_gpu_time,
                        true);
     WriteSettingGlobal(QStringLiteral("force_30fps_mode"), Settings::values.force_30fps_mode,