[Bug testsuite/67905] running the libstdc++ testsuite as root removed /dev/null from my system

[redi at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=67905

--- Comment #4 from Jonathan Wakely <redi at gcc dot gnu.org> ---
I don't see anything in the libstdc++ testsuite that would remove it anyway, so
I'm going to blame DejaGnu or OS X.