ALSA: emu10k1: fix handling of half-loop interrupts

We'd try to iterate the voices twice without resetting the pointer.
This went unnoticed, because the code isn't actually in use.

Amends commit 27ae958c ("emu10k1 driver - add multichannel device
hw:x,3 [2-8/8]").
Signed-off-by: Oswald Buddenhagen <oswald.buddenhagen@gmx.de>
Link: https://lore.kernel.org/r/20230518093047.3697887-4-oswald.buddenhagen@gmx.deSigned-off-by: Takashi Iwai <tiwai@suse.de>

sound/pci/emu10k1/irq.c

@@ -47,12 +47,13 @@ irqreturn_t snd_emu10k1_interrupt(int irq, void *dev_id)
 			status &= ~(IPR_VOLINCR|IPR_VOLDECR|IPR_MUTE);
 		}
 		if (status & IPR_CHANNELLOOP) {
+			struct snd_emu10k1_voice *pvoice;
 			int voice;
 			int voice_max = status & IPR_CHANNELNUMBERMASK;
 			u32 val;
-			struct snd_emu10k1_voice *pvoice = emu->voices;
 
 			val = snd_emu10k1_ptr_read(emu, CLIPL, 0);
+			pvoice = emu->voices;
 			for (voice = 0; voice <= voice_max; voice++) {
 				if (voice == 0x20)
 					val = snd_emu10k1_ptr_read(emu, CLIPH, 0);
@@ -68,6 +69,7 @@ irqreturn_t snd_emu10k1_interrupt(int irq, void *dev_id)
 				pvoice++;
 			}
 			val = snd_emu10k1_ptr_read(emu, HLIPL, 0);
+			pvoice = emu->voices;
 			for (voice = 0; voice <= voice_max; voice++) {
 				if (voice == 0x20)
 					val = snd_emu10k1_ptr_read(emu, HLIPH, 0);