bug#18741: xf86-video-ati fails to build on all platforms

[Mark H Weaver]

xf86-video-ati fails to build on all platforms.  See:

  http://hydra.gnu.org/job/gnu/master/xf86-video-ati-6.14.4.x86_64-linux
  http://hydra.gnu.org/job/gnu/master/xf86-video-ati-6.14.4.i686-linux

     Mark