ASoC: codecs: wcd938x: add Multi Button Headset Control support

WCD938x has Multi Button Headset Control hardware to support Headset
insertion, type detection, 8 headset buttons detection, Over Current
detection and Impedence measurements.
This patch adds support for this using wcd-mbhc apis.

Signed-off-by: Srinivas Kandagatla <srinivas.kandagatla@linaro.org>
Link: https://lore.kernel.org/r/20210716105918.7301-1-srinivas.kandagatla@linaro.org


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