ASoC: Fixup Cirrus SX control usage

Merge series from Charles Keepax <ckeepax@opensource.cirrus.com>:

Mostly the usage of the SX controls seems to match the lowest gain
value + number of gain levels expected. The one notable exception
there being cs53l30 as David noted. However, there are a couple of
other places where the minimum value/TLVs are slightly incorrectly
specified.