Don't let ATF call basename() and dirname() in a non-standard way.

[ed]

Summary

POSIX basename() and dirname() are allowed to overwrite the input
buffer. The advantage of implementing it that way is that the functions
can be thread-safe, as they don't store the result in a global buffer.

It looks like ATF wants to call basename() and dirname() in the
non-standard way where the argument is of type "const char *". This
change disables the calls to basename() and dirname(), which only seems
to affect the formatting of some rare debug/error messages.

[ngie]

The change looks good to me.

It's testing invariants in atf-c(3) when NDEBUG isn't defined (which seems backwards to be honest...), to make sure that basename(3)/dirname(3) are functioning as expected, so the net effect of the proposed change is ok.

[jmmv]

ngie is right in that basename and dirname are used for sanity-checking purposes. Why this is in the live code path and not in tests... doesn't make much sense, and I guess this could all be dropped.

But ngie, why do you say that this is being tested when NDEBUG is set? The check is gated by the INV macro, which is only defined in the !NDEBUG case.