Gdk initialization ends up calling epoxy GLX api, which calls exit()
if libGL.so.1 is not present. In practice this prevents all GTK+
applications from starting if GLX is not present.
If opengl and x11 distro features are set, make gtk+3 RDEPEND on libgl.
If opengl and x11 distro features are not set, use #ifdef to prevent
the GL initialization.
Remove libgl dependency from gtk3-demo: it can now run without
libgl (although trying to run the glarea demo will exit in that case).
[YOCTO #8529]
Signed-off-by: Jussi Kukkonen <jussi.kukkonen@intel.com> Signed-off-by: Ross Burton <ross.burton@intel.com>
