ASoC: ops: Fix bounds check for _sx controls

For _sx controls the semantics of the max field is not the usual one, max
is the number of steps rather than the maximum value. This means that our
check in snd_soc_put_volsw_sx() needs to just check against the maximum
value.

Fixes: 4f1e50d6

 ("ASoC: ops: Reject out of bounds values in snd_soc_put_volsw_sx()")
Signed-off-by: Mark Brown <broonie@kernel.org>
Link: https://lore.kernel.org/r/20220511134137.169575-1-broonie@kernel.org
Signed-off-by: Mark Brown <broonie@kernel.org>