Xwayland is using a copy of the CVT generator found in Xorg.
Rather than duplicating the code within the xserver tree, use the
libxcvt implementation instead.
Closes: https://gitlab.freedesktop.org/xorg/xserver/-/issues/1142
Signed-off-by: Olivier Fourdan <ofourdan@redhat.com>
Reviewed-by: Matt Turner <mattst88@gmail.com>