[Bug testsuite/85326] `make check` fails with `--disable-bootstrap` and `--enable-languages=c`

[jakub at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=85326

--- Comment #3 from Jakub Jelinek <jakub at gcc dot gnu.org> ---
(In reply to ktkachov from comment #2)
> I think some of the arm tests could well be C tests rather than C++. So
> maybe just renaming the file to *.c will be enough.
> 
> For the ones that are truly C++ is the recommended approach moving them to
> g++.dg and guarding them on the target?

That is what we used to do for decades, e.g. I see around 150 x86 tests in
g++.dg/*/
As I wrote elsewhere, adding g++.target/*/ directories is another option, but
I'd say it should be GCC9 thing if we decide to do that.