Convert the NAU8315 audio CODEC bindings to DT schema.

Signed-off-by: David Lin <CTLIN0@nuvoton.com
Reviewed-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org
Link: https://lore.kernel.org/r/20230516054944.1081808-1-CTLIN0@nuvoton.com
Signed-off-by: Mark Brown <broonie@kernel.org