ASoC: da7213: Add DAI DAPM event to control DAI clocks

Currently, when Codec is I2S master DAI clocks are continuously
generated even if all audio streams have stopped. To improve
efficiency, control of the DAI clocks for master mode have been
moved to a DAPM widget event so they're only enabled as required.

Signed-off-by: Adam Thomson <Adam.Thomson.Opensource@diasemi.com>
Signed-off-by: Mark Brown <broonie@kernel.org>