ASoC: Add PCM1681 codec driver.

PCM1681 can be controlled via I2C, SPI or in bootstrap mode (no control mode). This code add
support only for I2C mode.

Signed-off-by: Marek Belisko <marek.belisko@streamunlimited.com>
Signed-off-by: Mark Brown <broonie@linaro.org>
4 files changed