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>
diff --git a/sound/drivers/opl4/opl4_synth.c b/sound/drivers/opl4/opl4_synth.c
index 74f6e53..49b9e24 100644
--- a/sound/drivers/opl4/opl4_synth.c
+++ b/sound/drivers/opl4/opl4_synth.c
@@ -467,7 +467,7 @@
 	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);
 }