spi: dt-bindings: allwinner: simplify with unevaluatedProperties

spi: dt-bindings: allwinner: simplify with unevaluatedProperties

Remove properties already mentioned by common spi-controller.yaml and
switch to unevaluatedProperties:false to achieve same functional effect.
This makes the binding a bit smaller.  Similarly there is no need to
allow additionalProperties for children, because spi-controller.yaml
already does it.

Signed-off-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
Link: https://lore.kernel.org/r/20230601095908.563865-1-krzysztof.kozlowski@linaro.org
Signed-off-by: Mark Brown <broonie@kernel.org>