ALSA: korg1212: Support PCM sync_stop

The driver invokes snd_pcm_period_elapsed() simply from the interrupt
handler.  Set card->sync_irq for enabling the missing sync_stop PCM
operation.

Link: https://lore.kernel.org/r/20191210063454.31603-26-tiwai@suse.deSigned-off-by: Takashi Iwai <tiwai@suse.de>

sound/pci/korg1212/korg1212.c

@@ -2237,6 +2237,7 @@ static int snd_korg1212_create(struct snd_card *card, struct pci_dev *pci,
         }
 
         korg1212->irq = pci->irq;
+	card->sync_irq = korg1212->irq;
 
 	pci_set_master(korg1212->pci);