ASoC: cs35l41: Correct amp_gain_tlv values

The current analog gain TLV seems to have completely incorrect values in
it. The gain starts at 0.5dB, proceeds in 1dB steps, and has no mute
value, correct the control to match.

Signed-off-by: Charles Keepax <ckeepax@opensource.cirrus.com>
Link: https://lore.kernel.org/r/20230823085308.753572-1-ckeepax@opensource.cirrus.com
Signed-off-by: Mark Brown <broonie@kernel.org>