ASoC: mediatek: mt8183: switch tdm pins gpio function when playback on or off

Pull TDM pins down when TDM BE shutdown to avoid current leakage.

Signed-off-by: Jiaxin Yu <jiaxin.yu@mediatek.com>
Link: https://lore.kernel.org/r/1566478261-13464-2-git-send-email-jiaxin.yu@mediatek.com


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