dt-bindings: pinctrl: aspeed: Allow only defined pin mux node properties

dt-bindings: pinctrl: aspeed: Allow only defined pin mux node properties

The Aspeed pinctrl bindings are missing an additionalProperties/
unevaluatedProperties schemas on the child pin mux nodes which means any
undefined properties are allowed. In addition, using
'additionalProperties' for child nodes with any name works better than a
pattern matching everything with an if/then schema to select nodes only.

With 'additionalProperties' added, 'pins' and 'bias-disable'
properties need to be added as they were not defined. A $ref to
pinmux-node.yaml which defines the common property types was also
missing.

Signed-off-by: Rob Herring <robh@kernel.org>
Reviewed-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
Link: https://lore.kernel.org/r/20230819010907.916061-1-robh@kernel.org
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>