ASoC: codecs: Add support for the Renesas IDT821034 codec

The Renesas IDT821034 codec is four channel PCM codec with on-chip
filters and programmable gain setting.
It also provides SLIC (Subscriber Line Interface Circuit) signals as
GPIOs.

Signed-off-by: Herve Codina <herve.codina@bootlin.com>
Link: https://lore.kernel.org/r/20230126085137.375814-3-herve.codina@bootlin.com


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