Add a way to disable aotstats statistics file generations

QML statistics files are generated in every project build by default. It would have been nice if we could disable generation of .aotstats files (If they are not explicitly necessary for the build of every QML project). It takes a lot of time to build and debug apps. I can enable them with the all_aotstats CMake target if I want already, right? Plus, I couldn't find a way to disable them no matter what. Is there a way to even disable them? I think this might be a bug If I am not mistaken.