ASoC: soc-utils: Transition to the faux device interface

ASoC: soc-utils: Transition to the faux device interface

The ASoC soc-utils driver does not require the creation of a platform
device. Originally, this approach was chosen for simplicity when the
driver was first implemented.

With the introduction of the lightweight faux device interface, we now
have a more appropriate alternative. Migrate the driver to utilize the
faux bus, given that the platform device it previously created was not
a real one anyway. This will simplify the code, reducing its footprint
while maintaining functionality.

Cc: Mark Brown <broonie@kernel.org>
Cc: Takashi Iwai <tiwai@suse.com>
Cc: linux-sound@vger.kernel.org
Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>
Link: https://patch.msgid.link/20250317-plat2faux_dev-v1-6-5fe67c085ad5@arm.com
Signed-off-by: Mark Brown <broonie@kernel.org>