ASoC: SDCA: Add SDCA Control parsing

Each SDCA Entity will contain a number of Controls, these are
basically equivalent to registers. Although a single Control will only
ever contain a single field. Some of these would map directly to ALSA
controls once more of the SDCA class driver is implemented. These
controls are parsed out of the DisCo ACPI tables.

One small todo here is that each Control can have multiple
sub-entries (Control Numbers), these are typically used to represent
channels. Whilst support is present for these, currently the
ACPI properties that would allow differing defaults for each channel
are not parsed. But there is nothing here that should prevent that
being added in the future.

Signed-off-by: Charles Keepax <ckeepax@opensource.cirrus.com>
Reviewed-by: Pierre-Louis Bossart <pierre-louis.bossart@linux.dev>
Link: https://patch.msgid.link/20250205113801.3699902-6-ckeepax@opensource.cirrus.com


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