dt-bindings: ata: drop minItems equal to maxItems

minItems, if missing, are implicitly equal to maxItems, so drop
redundant piece to reduce size of code.

Signed-off-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
Reviewed-by: Laurent Pinchart <laurent.pinchart+renesas@ideasonboard.com>
Acked-by: Damien Le Moal <damien.lemoal@opensource.wdc.com>
Link: https://lore.kernel.org/r/20220825113334.196908-2-krzysztof.kozlowski@linaro.org


Signed-off-by: Rob Herring <robh@kernel.org>