[Bug analyzer/106390] Support gsl::owner<T> and/or [[gnu::owner]] attribute in -fanalyzer

[vultkayn at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=106390

--- Comment #5 from Benjamin Priour <vultkayn at gcc dot gnu.org> ---

> I agree that this would be a problem, but instead of implying that we need
> two attributes, I think this implies that we should not try to use
> [[gsl::owner]] for shared ownership. If you don't try to use it for both,
> the problem doesn't exist.

If we discard tracking shared ownership, it indeed removes a lot of complexity,
and I agree we can stick to [[gsl::owner]], and tracking moves of resources
becomes much simpler.

I'll go with that for now, see what tests I can do, dig a little bit.