[Fontconfig] fc-cache sometimes fails

[plam at MIT.EDU (Patrick Lam)]

Mike FABIAN wrote:
>     mfabian@magellan:/tmp/test$ fc-cache -v .
>     fc-cache: ".": caching, 0 fonts, 0 dirs
>     fc-cache: failed

Oops, I misinterpreted the unlink() return value.  Fixed.

pat