[audio_core, hle/services, video_core/compute] Inline std::unique_ptr<> allocs into std::optional<>

Signed-off-by: lizzie <lizzie@eden-emu.dev>

src/audio_core/audio_out_manager.cpp

@@ -40,8 +40,7 @@ void Manager::ReleaseSessionId(const size_t session_id) {
 Result Manager::LinkToManager() {
     std::scoped_lock l{mutex};
     if (!linked_to_manager) {
-        AudioManager& manager{system.AudioCore().GetAudioManager()};
-        manager.SetOutManager(std::bind(&Manager::BufferReleaseAndRegister, this));
+        system.AudioCore().GetAudioManager().SetOutManager(std::bind(&Manager::BufferReleaseAndRegister, this));
         linked_to_manager = true;
     }