dt-bindings: pinctrl: qcom: create common LPASS LPI schema

Just like regular TLMM pin controllers in Qualcomm SoCs, the Low Power
Audio SubSystem (LPASS) Low Power Island (LPI) TLMM blocks share a lot
of properties, so common part can be moved to separate schema to reduce
code duplication and make reviewing easier.

Except the move of common part, this introduces effective changes:
1. To all LPASS LPI bindings: Reference pinmux-node.yaml in each pin
   muxing and configuration node, to bring definition of "function" and
   "pins" properties.

2. qcom,sc7280-lpass-lpi-pinctrl: Reference pinctrl.yaml in top leve.

Signed-off-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
Reviewed-by: Rob Herring <robh@kernel.org>
Link: https://lore.kernel.org/r/20231208215534.195854-1-krzysztof.kozlowski@linaro.org


Signed-off-by: Linus Walleij <linus.walleij@linaro.org>