ALSA: aloop: Add control element for getting the access mode

Add new control element 'PCM Slave Access Mode' which shows the access
mode (interleaved/non-interleaved) for the PCM playing device. Add
corresponding control change notification calls.

Signed-off-by: Ivan Orlov <ivan.orlov0322@gmail.com>
Reviewed-by: Jaroslav Kysela <perex@perex.cz>
Link: https://lore.kernel.org/r/20230927113555.14877-2-ivan.orlov0322@gmail.com


Signed-off-by: Takashi Iwai <tiwai@suse.de>