ASoC: Extend wm_adsp so cs35l56 can suppress controls

ASoC: Extend wm_adsp so cs35l56 can suppress controls

Merge series from Simon Trimmer <simont@opensource.cirrus.com>:

This pair of patches extend wm_adsp to add a callback that can be used
to control whether ALSA controls are added and then tweak cs35l56 to use
it to suppress controls made from firmware coefficients.