ASoC: mediatek: mt8186: support hw gain in platform driver

Add mt8186 hw gain dai driver.

Signed-off-by: Jiaxin Yu <jiaxin.yu@mediatek.com>
Reviewed-by: AngeloGioacchino Del Regno <angelogioacchino.delregno@collabora.com>
Link: https://lore.kernel.org/r/20220523132858.22166-7-jiaxin.yu@mediatek.com


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