[Reproducible-builds] Link Time Optimization breaks reproducible builds

[conchur at web.de]

> GCC is definitely full of unknown features. Could you try again adding
> the `-save-temps` option? It seems to make the intermediate file names
> deterministic according to my tests.

Yes, I've just tested it and it definitely works around the problem.
So it is still a problem of the intermediate file names.

I only use it (-save-temps=obj) for the linker step. The extra
file is  libmupen64plus.so.2.0.res
It is also still necessary to use -flto-partition=none

Regards,
Conchúr Navid