ASoC: dt-bindings: Convert Allwinner A23 analog codec to a schema

ASoC: dt-bindings: Convert Allwinner A23 analog codec to a schema

The Allwinner A23 SoC and later have an embedded audio codec that uses a
separate controller to drive its analog part, which is supported in Linux,
with a matching Device Tree binding.

Now that we have the DT validation in place, let's convert the device tree
bindings for that controller over to a YAML schemas.

Signed-off-by: Maxime Ripard <maxime.ripard@bootlin.com>
Reviewed-by: Rob Herring <robh@kernel.org>
Link: https://lore.kernel.org/r/20190906151221.3148-2-mripard@kernel.org
Signed-off-by: Mark Brown <broonie@kernel.org>