Stop saving undo buffer (and associated .dtm, and .sav) when starting playing back a movie from save state. This is completely useless, and just wastes time copying save states around.

Source/Core/Core/Src/State.cpp

@@ -385,6 +385,7 @@ void LoadAs(const std::string& filename)
 	g_loadDepth++;
 
 	// Save temp buffer for undo load state
+	if (!Movie::IsJustStartingRecordingInputFromSaveState())
 	{
 		std::lock_guard<std::mutex> lk(g_cs_undo_load_buffer);
 		SaveToBuffer(g_undo_load_buffer);