ASoC: tas2764: expose die temp to hwmon

ASoC: tas2764: expose die temp to hwmon

TAS2764 contains an ADC that reports the chip's die temperature.
The temperature in degrees Celsius is yielded by subtracting 93
from the raw value reported by the ADC.

Expose the codec die temperature to the hwmon interface.

The chip will initialise the temperature register to 2.6 *C
to avoid triggering over temp protection. As the ADC is powered
down during software shutdown, this value will persist until the
chip is fully powered up (e.g. when the PCM it's attached to is
opened). When the chip is powered back down, the last value sampled
will persist in the register.

Co-developed-by: Martin Povišer <povik+lin@cutebit.org>
Signed-off-by: Martin Povišer <povik+lin@cutebit.org>
Signed-off-by: James Calligeros <jcalligeros99@gmail.com>
Link: https://patch.msgid.link/20250406-apple-codec-changes-v5-8-50a00ec850a3@gmail.com
Signed-off-by: Mark Brown <broonie@kernel.org>