ASoC: tlv320adcx140: power on/off the device on demand

ASoC: tlv320adcx140: power on/off the device on demand

The tlv320adcx140 can be connected to controllable AVDD/IOVDD regulators
which when disabled will reset the registers to their default.  In
preparation for that switch to register writes to cache only when
powered off and sync the cached values to the registers when powered
back on.

Signed-off-by: Emil-Juhl <juhl.emildahl@gmail.com>
Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>
Link: https://patch.msgid.link/20260113-sound-soc-codecs-tvl320adcx140-v4-5-8f7ecec525c8@pengutronix.de
Signed-off-by: Mark Brown <broonie@kernel.org>