ALSA: hda - proc - introduce Control: lines to show mixer<->NID assignment

This is an initial patch to show universal control<->NID assigment in
proc codec file. The change helps to debug codec related problems.

Signed-off-by: Jaroslav Kysela <perex@perex.cz>
Signed-off-by: Takashi Iwai <tiwai@suse.de>
diff --git a/sound/pci/hda/patch_realtek.c b/sound/pci/hda/patch_realtek.c
index 8c04e0e..fff9de2 100644
--- a/sound/pci/hda/patch_realtek.c
+++ b/sound/pci/hda/patch_realtek.c
@@ -2461,7 +2461,8 @@
 			if (!kctl)
 				return -ENOMEM;
 			kctl->private_value = spec->beep_amp;
-			err = snd_hda_ctl_add(codec, kctl);
+			err = snd_hda_ctl_add(codec,
+					get_amp_nid_(spec->beep_amp), kctl);
 			if (err < 0)
 				return err;
 		}