[ALSA] aoa: set device pointer in pcms

This patch makes a few whitespace cleanups and makes i2sbus assign the new
struct device pointer in struct snd_pcm so that the proper device symlink
shows up in sysfs.

Signed-off-by: Johannes Berg <johannes@sipsolutions.net>
Signed-off-by: Takashi Iwai <tiwai@suse.de>
Signed-off-by: Jaroslav Kysela <perex@suse.cz>