ASoC: tas2764: Drop conflicting set_bias_level power setting

The driver is setting the PWR_CTRL field in both the set_bias_level
callback and on DAPM events of the DAC widget (and also in the
mute_stream method). Drop the set_bias_level callback altogether as the
power setting it does is in conflict with the other code paths.

(This mirrors commit c8a6ae3fe1c8 ("ASoC: tas2770: Drop conflicting
set_bias_level power setting") which was a fix to the tas2770 driver.)

Fixes: 827ed8a0

 ("ASoC: tas2764: Add the driver for the TAS2764")
Signed-off-by: Martin Povišer <povik+lin@cutebit.org>
Link: https://lore.kernel.org/r/20220825140241.53963-3-povik+lin@cutebit.org
Signed-off-by: Mark Brown <broonie@kernel.org>