ASoC: adau1701: add regulator consumer support

The adau1701 has two power domains, DVDD and AVDD.
Enable them both as long as the codec is in use.

Signed-off-by: Pascal Huerst <pascal.huerst@gmail.com>
Acked-by: Lars-Peter Clausen <lars@metafoo.de>
Signed-off-by: Mark Brown <broonie@kernel.org>