ASoC: mediatek: mt6358: save PGA for mixer control

mt6358_amic_disable() resets PGA to 0.

Save the gain settings from mixer control and restore them when using
the microphone.

Signed-off-by: Tzung-Bi Shih <tzungbi@google.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
1 file changed