ASoC: codecs: jz4725b: fix reported volume for Master ctl

DAC volume control is the Master Playback Volume at the moment
and it reports wrong levels in alsamixer and other alsa apps.

The patch fixes that, as stated in manual on the jz4725b SoC
(16.6.3.4 Programmable attenuation: GOD) the ctl range varies
from -22.5dB to 0dB with 1.5dB step.

Signed-off-by: Siarhei Volkau <lis8215@gmail.com>
Link: https://lore.kernel.org/r/20221016132648.3011729-3-lis8215@gmail.com
Signed-off-by: Mark Brown <broonie@kernel.org>