ASoC: rt5677: depop stereo dac

Upon enabling the ASRC DAC we need a delay to avoid popping the
speakers.

Signed-off-by: Curtis Malainey <cujomalainey@chromium.org>
Cc: Ross Zwisler <zwisler@chromium.org>
Tested-by: Ross Zwisler <zwisler@google.com>
Signed-off-by: Mark Brown <broonie@kernel.org>