ASoC: SDCA: Move SDCA search functions and export

ASoC: SDCA: Move SDCA search functions and export

The ASoC code for SDCA contains several helper functions that search for
controls/ranges/etc. As the code evolves these helpers are likely to be
useful to anything interacting with the stored DisCo data. Move the
helpers into sdca_function.c and export them so other modules can also
use them.

Signed-off-by: Charles Keepax <ckeepax@opensource.cirrus.com>
Reviewed-by: Pierre-Louis Bossart <pierre-louis.bossart@linux.dev>
Link: https://patch.msgid.link/20250707124155.2596744-4-ckeepax@opensource.cirrus.com
Signed-off-by: Mark Brown <broonie@kernel.org>