gdk-x11-3.0.pc, and builds that should fail

[Frederic Peters <fpeters gnome org>]

Hello,

gdk-x11-3.0.pc has been removed from gtk+, but jhbuild being what it
is, that file won't get removed from jhbuild installation prefix, and
modules depending of its presence won't start failing (and won't get
fixed as fast).

-> rm $prefix/lib/pkg-config/gdk-x11-3.0.pc


Cheers,

        Frederic