ASoC: cs42l51: Correct minimum value for SX volume control

ASoC: cs42l51: Correct minimum value for SX volume control

The minimum value for the PGA Volume is given as 0x1A, however the
values from there to 0x19 are all the same volume and this is not
represented in the TLV structure. The number of volumes given is correct
so this leads to all the volumes being shifted. Move the minimum value
up to 0x19 to fix this.

Signed-off-by: Charles Keepax <ckeepax@opensource.cirrus.com>
Link: https://lore.kernel.org/r/20220602162119.3393857-7-ckeepax@opensource.cirrus.com
Signed-off-by: Mark Brown <broonie@kernel.org>