ALSA: aaci: Delete unused variable in aaci_do_suspend

The variable aaci is not used anymore and can be deleted.

Fixes: 792a6c51

 ("[ALSA] Fix PM support")
Signed-off-by: Thomas Weißschuh <thomas.weissschuh@linutronix.de>
Link: https://lore.kernel.org/r/20240312-aaci-unused-v1-1-09be643f67c2@linutronix.de
Signed-off-by: Takashi Iwai <tiwai@suse.de>