As Xwayland is usually spawned by the Wayland server/compositor, its
command line options are not always adjustable.
Yet, if EGLStream is not supported in a given Xwayland build, the option
will do nothing (yet we must still accept it otherwise Xwayland would
refuse to run if the Wayland compositor uses it).
If Xwayland was built without support for EGLStream, there is not point
in showing the option in the help message though.
Signed-off-by: Olivier Fourdan <ofourdan@redhat.com>
Reviewed-by: Martin Peres <martin.peres@mupuf.org>