ASoC: cros_ec_codec: Support setting bclk ratio

Support setting bclk ratio from machine drivers.

Signed-off-by: Yu-Hsuan Hsu <yuhsuan@chromium.org>
Reviewed-by: Tzung-Bi Shih <tzungbi@google.com>
Link: https://lore.kernel.org/r/20200125162917.247485-1-yuhsuan@chromium.org


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