ALSA: hda - Add reboot notifier to each codec

Add reboot notifier to each codec so that it can do some workarounds
needed for reboot.

So far, patch_sigmatel.c calls its shutup routine for avoiding noises
at reboot on some HP machines.

References: Novell bnc#544779
	http://bugzilla.novell.com/show_bug.cgi?id=544779

Signed-off-by: Takashi Iwai <tiwai@suse.de>
diff --git a/sound/pci/hda/hda_intel.c b/sound/pci/hda/hda_intel.c
index 55c7da3..0d3e0c9 100644
--- a/sound/pci/hda/hda_intel.c
+++ b/sound/pci/hda/hda_intel.c
@@ -2150,6 +2150,7 @@
 static int azx_halt(struct notifier_block *nb, unsigned long event, void *buf)
 {
 	struct azx *chip = container_of(nb, struct azx, reboot_notifier);
+	snd_hda_bus_reboot_notify(chip->bus);
 	azx_stop_chip(chip);
 	return NOTIFY_OK;
 }