ALSA: aica: Remove unused variable

The variable is never referenced in the code, just remove it

Signed-off-by: Zhu Jun <[e-mail]>
Link: https://patch.msgid.link/[e-mail]
Signed-off-by: Takashi Iwai <[e-mail]>

sound/sh/aica.c

···
 static void spu_begin_dma(struct snd_pcm_substream *substream)
 {
 	struct snd_card_aica *dreamcastcard;
-	struct snd_pcm_runtime *runtime;
-	runtime = substream->runtime;
 	dreamcastcard = substream->pcm->private_data;
 	/*get the queue to do the work */
 	schedule_work(&(dreamcastcard->spu_dma_work));