bug#7957: build failure due to missing fontconfig's FC_DUAL

[Glenn Morris]

Package: emacs
Version: 23.2.93
Severity: important

23.2.93 pretest fails to build on RHEL 4.8:

  ftfont.c: In function `ftfont_open':
  ftfont.c:1265: error: `FC_DUAL' undeclared (first use in this function)

Re-configuring using --without-xft worked.

This system has fontconfig 2.2.3. This passes configure's check for
version >= 2.2.0. However, it looks like FC_DUAL was not added until
version 2.3.0. Perhaps the version configure tests for should be bumped.

(But since I personally don't care about using dual-width fonts with
Emacs, it might be nice if I could still use the older fontconfig.)