ALSA: Fix missing KERN_* prefix to printk in sound/pci

Signed-off-by: Takashi Iwai <tiwai@suse.de>
diff --git a/sound/pci/ak4531_codec.c b/sound/pci/ak4531_codec.c
index 0f819dd..fd135e3 100644
--- a/sound/pci/ak4531_codec.c
+++ b/sound/pci/ak4531_codec.c
@@ -51,7 +51,8 @@
 	int idx;
 	
 	for (idx = 0; idx < 0x19; idx++)
-		printk("ak4531 0x%x: 0x%x\n", idx, ak4531->regs[idx]);
+		printk(KERN_DEBUG "ak4531 0x%x: 0x%x\n",
+		       idx, ak4531->regs[idx]);
 }
 
 #endif