dt-bindings: net: asix,ax88796c: allow SPI peripheral properties

dt-bindings: net: asix,ax88796c: allow SPI peripheral properties

The AX88796C device node on SPI bus can use SPI peripheral properties in
certain configurations:

  exynos3250-artik5-eval.dtb: ethernet@0: 'controller-data' does not match any of the regexes: 'pinctrl-[0-9]+'

Signed-off-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
Acked-by: Rob Herring <robh@kernel.org>
Link: https://lore.kernel.org/r/20230120144329.305655-1-krzysztof.kozlowski@linaro.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>