ALSA: Kill snd_assert() in other places

Kill snd_assert() in other places, either removed or replaced with
if () with snd_BUG_ON().

Signed-off-by: Takashi Iwai <tiwai@suse.de>
Signed-off-by: Jaroslav Kysela <perex@perex.cz>

sound/drivers/opl4/opl4_synth.c

@@ -467,7 +467,7 @@ static struct opl4_voice *snd_opl4_get_voice(struct snd_opl4 *opl4)
 	if (!list_empty(&opl4->off_voices))
 		return list_entry(opl4->off_voices.next, struct opl4_voice, list);
 	/* then get the oldest key-on voice */
-	snd_assert(!list_empty(&opl4->on_voices), );
+	snd_BUG_ON(list_empty(&opl4->on_voices));
 	return list_entry(opl4->on_voices.next, struct opl4_voice, list);
 }