package/efl: add OpenGL/OpenGLES support

package/efl: add OpenGL/OpenGLES support

Allow to enable graphic acceleration using OpenGL or OpenGLES with efl
libraries.

The full OpenGL option depend on X11, because full OpenGL means GLX,
which means X11. Also select efl xlib support when full OpenGL is
selected.

Enable OpenGL ES when EGL API is enabled, otherwise the build fail with
this error:
configure: error: OpenGL ES requires EGL, please add --enable-egl to your configure options to switch to EGL + OpenGL ES.

With the upcomming Wayland support in EFL Buildroot packaging,
OpenGL ES support is recommended.

Signed-off-by: Romain Naour <romain.naour@gmail.com>
[Thomas:
 - use a single ifeq/else ifeq/else ifeq/endif block
 - remove the "default" for the choice, move the "none" choice at the
   end, and simply rely on the first choice having its dependencies met
   being automatically enable by kconfig. So OpenGL first, then
   OpenGLES, and then none.]
Signed-off-by: Thomas Petazzoni <thomas.petazzoni@free-electrons.com>