ASoC: dt-bindings: Convert Allwinner A64 analog codec to a schema

ASoC: dt-bindings: Convert Allwinner A64 analog codec to a schema

The Allwinner A64 SoC has 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>
Link: https://lore.kernel.org/r/20190828125209.28173-5-mripard@kernel.org
Reviewed-by: Rob Herring <robh@kernel.org>
Signed-off-by: Mark Brown <broonie@kernel.org>