ASoC: SOF: remove const qualifier for 'struct snd_sof_dsp_ops'

ASoC: SOF: remove const qualifier for 'struct snd_sof_dsp_ops'

Now that we start having multiple platforms with minor variants, the
use of the const qualifier for 'dsp_ops' is starting to be
sub-optimal: the structures are copied across platforms, with only a
couple of members that differ.

This patch removes the const qualifier without any functionality
changes, and adds an optional initialization callback. In follow-up
patches, the dsp_ops will revisited for Intel HDaudio platforms, with
the differences added programmatically over a common baseline.

Signed-off-by: Pierre-Louis Bossart <pierre-louis.bossart@linux.intel.com>
Reviewed-by: Ranjani Sridharan <ranjani.sridharan@linux.intel.com>
Reviewed-by: Péter Ujfalusi <peter.ujfalusi@linux.intel.com>
Reviewed-by: Kai Vehmanen <kai.vehmanen@linux.intel.com>
Reviewed-by: Rander Wang <rander.wang@intel.com>
Reviewed-by: Bard Liao <yung-chuan.liao@linux.intel.com>
Link: https://lore.kernel.org/r/20220414184817.362215-9-pierre-louis.bossart@linux.intel.com
Signed-off-by: Mark Brown <broonie@kernel.org>