ASoC: Convert jz4740-i2s doc to YAML

Convert the textual binding documentation for the AIC (AC97/I2S
Controller) of Ingenic SoCs to a YAML schema, and add the new compatible
strings in the process.

Signed-off-by: Paul Cercueil <paul@crapouillou.net>
Reviewed-by: Rob Herring <robh@kernel.org>
Link: https://lore.kernel.org/r/20200306222931.39664-1-paul@crapouillou.net


Signed-off-by: Mark Brown <broonie@kernel.org>