dt-bindings: pinctrl: Add missing (unevaluated|additional)Properties on child nodes

In order to ensure only documented properties are present, node schemas
must have unevaluatedProperties or additionalProperties set to false
(typically).

Signed-off-by: Rob Herring <robh@kernel.org>
Reviewed-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
Link: https://lore.kernel.org/r/20220823145649.3118479-6-robh@kernel.org
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>

dt-bindings: pinctrl: Add binding for BCM4908 pinctrl

It's hardware block that is part of every SoC from BCM4908 family.

Signed-off-by: Rafał Miłecki <rafal@milecki.pl>
Reviewed-by: Rob Herring <robh@kernel.org>
Link: https://lore.kernel.org/r/20220124102243.14912-1-zajec5@gmail.com
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>