ALSA: aoa: convert bus code to use dev_groups

The dev_attrs field of struct bus_type is going away, use dev_groups instead.
This converts the soundbus code to use the correct field.

These modifications were made using Coccinelle.

Signed-off-by: Quentin Lambert <lambert.quentin@gmail.com>
Signed-off-by: Takashi Iwai <tiwai@suse.de>