ASoC: dt-bindings: Convert maxim,max98925 to DT schema

ASoC: dt-bindings: Convert maxim,max98925 to DT schema

Convert the Maxim Integrated MAX98925/MAX98926/MAX98927 speaker
amplifier bindings to DT schema format.  Changes during conversion:
1. Add "sound-dai-cells", already used by DTS.
2. Use "maxim,interleave-mode" instead previous "interleave-mode" and
   undocumented but used interleave_mode.

Signed-off-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
Link: https://lore.kernel.org/r/20230730201826.70453-1-krzysztof.kozlowski@linaro.org
Signed-off-by: Mark Brown <broonie@kernel.org>