Now all the regulators are disabled when entering into SND_SOC_BIAS_OFF
and enabled when coming back to SND_SOC_BIAS_STANDBY state. Currently this
runtime control happens only with suspend/resume as this patch does not
change the default idle behavior.

This patch manages all the regulators and reset since it seems that register
sync is needed even if only analog supplies AVDD and DRVDD are disabled.
This was noted when the system was running with idle behavior changed and
IOVDD and DVDD were on.

It is not known are all the registers needed to sync or only some subset of
them. Therefore patch plays safe and does always full shutdown/power-up.
Signed-off-by: Jarkko Nikula <jhnikula@gmail.com>
Acked-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
Signed-off-by: Liam Girdwood <lrg@slimlogic.co.uk>