firmware: cs_dsp: cs_dsp_coeff_write_ctrl() should report changed

ALSA callers need to know whether there was a change to the value so
that they can report a control write change correctly.

Signed-off-by: Simon Trimmer <simont@opensource.cirrus.com>
Signed-off-by: Richard Fitzgerald <rf@opensource.cirrus.com>
Link: https://lore.kernel.org/r/20221123165811.3014472-2-rf@opensource.cirrus.com


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