dt-bindings: pinctrl: Drop 'phandle' properties

dt-bindings: pinctrl: Drop 'phandle' properties

'phandle' properties are implicitly supported on all nodes, so it
shouldn't be listed in schemas.

dtschema had a bug where 'phandle' and other implicit properties weren't
being added under 'additionalProperties' schemas. That was fixed in
v2023.07 release.

Signed-off-by: Rob Herring <robh@kernel.org>
Reviewed-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
Link: https://lore.kernel.org/r/20230819010946.916772-1-robh@kernel.org
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>