ALSA: control-led: Integrate mute led trigger

ALSA: control-led: Integrate mute led trigger

This driver is the only one calling ledtrig_audio_set(), therefore
the LED audio trigger isn't usable standalone. So it makes sense
to fully integrate LED audio triger handling here.

The module aliases ensure that the driver is auto-loaded (if built
as module) if a LED device has one of the two audio triggers as
default trigger.

In addition disable building the old audio mute LED trigger.

Signed-off-by: Heiner Kallweit <hkallweit1@gmail.com>
Reviewed-by: Takashi Iwai <tiwai@suse.de>
Link: https://lore.kernel.org/r/107634e6-d9ad-4a9f-881d-1eb72ea1a5a7@gmail.com
Signed-off-by: Lee Jones <lee@kernel.org>