[video_core/engines/maxwell3d] memory inline DrawState to reduce indirection on hot paths (#3758)

usual indirection removal
helps very slightly to codegen

the idea is basically to reduce the amount of pointer deference overall in the code, and use idiomatic std::variant<>-isms to not rely on vtables/unique_ptr overhead
this should allow the compiler to emit better code
of course it's a tiny optimisation and only CPU side, but allows us to reduce indirection which is almost always a good thing

"but youre passing more parameters to the function!!!" its literally memoized into a register my friend

Signed-off-by: lizzie <lizzie@eden-emu.dev>
Reviewed-on: https://git.eden-emu.dev/eden-emu/eden/pulls/3758
Reviewed-by: crueter <crueter@eden-emu.dev>
Reviewed-by: MaranBr <maranbr@eden-emu.dev>

src/video_core/gpu_thread.cpp

@@ -63,9 +63,7 @@ ThreadManager::ThreadManager(Core::System& system_, bool is_async_)
 
 ThreadManager::~ThreadManager() = default;
 
-void ThreadManager::StartThread(VideoCore::RendererBase& renderer,
-                                Core::Frontend::GraphicsContext& context,
-                                Tegra::Control::Scheduler& scheduler) {
+void ThreadManager::StartThread(VideoCore::RendererBase& renderer, Core::Frontend::GraphicsContext& context, Tegra::Control::Scheduler& scheduler) {
     rasterizer = renderer.ReadRasterizer();
     thread = std::jthread(RunThread, std::ref(system), std::ref(renderer), std::ref(context),
                           std::ref(scheduler), std::ref(state));