ASoC: fsl-asoc-card: add nau8822 support

ASoC: fsl-asoc-card: add nau8822 support

This is for an imx6sx EVB which has a nau8822 codec connects to the
SSI2 interface, so add the nau8822 support in this machine driver.

Because the codec driver nau8822.c doesn't handle mclk enabling, here
adding a codec_priv->mclk for nau8822 and similar codecs which need to
enable the mclk in the machine driver, and enable the mclk in the
card_late_probe() conditionally.

Signed-off-by: Hui Wang <hui.wang@canonical.com>
Link: https://lore.kernel.org/r/Message-Id:
Signed-off-by: Mark Brown <broonie@kernel.org>