[Bug testsuite/80219] relative line numbers only working if gcc_{error,warning}_prefix defined

[pinskia at gcc dot gnu.org via Gcc-bugs]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=80219

--- Comment #6 from Andrew Pinski <pinskia at gcc dot gnu.org> ---
gcc_warning_prefix and gcc_error_prefix are still not set for the gnat
testsuite.