ASoC: dt-bindings: convert designware-i2s to dt-schema

Convert the Synopsys DesignWare I2S controller binding to dt-schema.
There was no listed maintainer but Jose Abreu was the last editor of the
txt binding so add him as maintainer.

Signed-off-by: Conor Dooley <conor.dooley@microchip.com>
Link: https://lore.kernel.org/r/20220701192300.2293643-4-conor@kernel.org


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