ASoC: wm_adsp: Separate wm_adsp specifics in cs_dsp_client_ops

This is preparation for moving the generic DSP support out of ASoC.
The event callbacks let the client add custom handling of events.

Signed-off-by: Simon Trimmer <simont@opensource.cirrus.com>
Signed-off-by: Charles Keepax <ckeepax@opensource.cirrus.com>
Link: https://lore.kernel.org/r/20210913160057.103842-16-simont@opensource.cirrus.com


Signed-off-by: Mark Brown <broonie@kernel.org>