ASoC: intel: sof_sdw: Add ability to have auxiliary devices

ASoC: intel: sof_sdw: Add ability to have auxiliary devices

Currently the sof_sdw machine driver assumes that all devices involved
in the sound card are connected through a DAI link. However for SDCA
devices we still want the HID (Human Interface Device, used for jack
buttons) to be part of the sound card, but it contains no DAI links.

Add support into the machine driver to specify a list of auxiliary
devices to merged into the card.

Reviewed-by: Bard Liao <yung-chuan.liao@linux.intel.com>
Signed-off-by: Charles Keepax <ckeepax@opensource.cirrus.com>
Link: https://patch.msgid.link/20251127163426.2500633-6-ckeepax@opensource.cirrus.com
Signed-off-by: Mark Brown <broonie@kernel.org>