[Fontconfig] Format of cache file are different on 32bit and 64bit system.

[Zhe Su]

Hi,
  Recently I found that format of fonts.cache-2 file are different on
32bit and 64bit system. It leads big performance issue for 32bit
applications on 32bit/64bit mixed system, like x86_64. Because 32bit
applications must re-create local cache file on startup, almost every
time.
  For more information, see https://bugzilla.novell.com/show_bug.cgi?id=160226

  Is it possible to unify the cache file format for both 32bit and 64bit system?

Regards
James Su