ASoC: mediatek: mt6358: Add "Dmic Mode Switch" kcontrol for switch DMIC mode.

ASoC: mediatek: mt6358: Add "Dmic Mode Switch" kcontrol for switch DMIC mode.

There are two hardware connection methods for DMICs on the MT6358. In cases
where more than two DMICs are used, we need to time-multiplex these DMICs.
Therefore, we need to dynamically switch the modes of these DMICs based on
the actual usage scenarios.

            ---- DMIC1
AU_VIN0 ---
            ---- DMIC2

AU_VIN2 --- ----DMIC3

When we want to use DMIC1/2, configure it to one-wire mode. When we want to
use DMIC1/3, configure it to two-wire mode.

Signed-off-by: Jiaxin Yu <jiaxin.yu@mediatek.com>
Link: https://patch.msgid.link/20240613020725.27874-1-jiaxin.yu@mediatek.com
Signed-off-by: Mark Brown <broonie@kernel.org>