ASoC: SDCA: Add code to parse Function information

ASoC: SDCA: Add code to parse Function information

Add a helper function to parse all the Function and Entity
information from ACPI. In SDCA each device may have several Functions
and each corresponds to a specific audio capability such as say
amplifier playback or microphone capture. Each Function then contains
a number of Entities that represent individual parts of the audio
signal chain and are linked together in a graph similar to DAPM.

Signed-off-by: Pierre-Louis Bossart <pierre-louis.bossart@linux.dev>
Signed-off-by: Charles Keepax <ckeepax@opensource.cirrus.com>
Reviewed-by: Pierre-Louis Bossart <pierre-louis.bossart@linux.dev>
Link: https://patch.msgid.link/20250205113801.3699902-3-ckeepax@opensource.cirrus.com
Signed-off-by: Mark Brown <broonie@kernel.org>