For some reason, unevaluatedProperties doesn't work and
additionalProperties is required. Fix it by switching to
additionalProperties.
Signed-off-by: Maxime Ripard <maxime@cerno.tech>
Link: https://lore.kernel.org/r/20210218152837.1080819-1-maxime@cerno.techSigned-off-by: Rob Herring <robh@kernel.org>