ALSA: atiixp: 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, as well as removing the superfluous synchronize_irq()
call.

Link: https://lore.kernel.org/r/20191210063454.31603-5-tiwai@suse.deSigned-off-by: Takashi Iwai <tiwai@suse.de>

sound/pci/atiixp.c

@@ -1597,8 +1597,8 @@ static int snd_atiixp_create(struct snd_card *card,
 		return -EBUSY;
 	}
 	chip->irq = pci->irq;
+	card->sync_irq = chip->irq;
 	pci_set_master(pci);
-	synchronize_irq(chip->irq);
 
 	if ((err = snd_device_new(card, SNDRV_DEV_LOWLEVEL, chip, &ops)) < 0) {
 		snd_atiixp_free(chip);

sound/pci/atiixp_modem.c

@@ -1227,8 +1227,8 @@ static int snd_atiixp_create(struct snd_card *card,
 		return -EBUSY;
 	}
 	chip->irq = pci->irq;
+	card->sync_irq = chip->irq;
 	pci_set_master(pci);
-	synchronize_irq(chip->irq);
 
 	if ((err = snd_device_new(card, SNDRV_DEV_LOWLEVEL, chip, &ops)) < 0) {
 		snd_atiixp_free(chip);