ALSA: hda/realtek - Set pcbeep amp for ALC668

Set the missing pcbeep default amp for ALC668.
Signed-off-by: Kailang Yang <kailang@realtek.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Takashi Iwai <tiwai@suse.de>

sound/pci/hda/patch_realtek.c

@@ -5118,6 +5118,7 @@ static int patch_alc662(struct hda_codec *codec)
 		case 0x10ec0272:
 		case 0x10ec0663:
 		case 0x10ec0665:
+		case 0x10ec0668:
 			set_beep_amp(spec, 0x0b, 0x04, HDA_INPUT);
 			break;
 		case 0x10ec0273: