[Bug ada/79309] incorrectly bounded calls to strncat in adaint.c

[ebotcazou at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=79309

--- Comment #4 from Eric Botcazou <ebotcazou at gcc dot gnu.org> ---
> I think it would be better to do:

Yes, this works for me.