ALSA: hda - No loopback on ALC299 codec

ALC299 has no loopback mixer, but the driver still tries to add a beep
control over the mixer NID which leads to the error at accessing it.
This patch fixes it by properly declaring mixer_nid=0 for this codec.

Bugzilla: https://bugzilla.kernel.org/show_bug.cgi?id=195775
Fixes: 28f1f9b2 ("ALSA: hda/realtek - Add new codec ID ALC299")
Cc: stable@vger.kernel.org
Signed-off-by: Takashi Iwai <tiwai@suse.de>

sound/pci/hda/patch_realtek.c

@@ -6465,8 +6465,11 @@ static int patch_alc269(struct hda_codec *codec)
 		break;
 	case 0x10ec0225:
 	case 0x10ec0295:
+		spec->codec_variant = ALC269_TYPE_ALC225;
+		break;
 	case 0x10ec0299:
 		spec->codec_variant = ALC269_TYPE_ALC225;
+		spec->gen.mixer_nid = 0; /* no loopback on ALC299 */
 		break;
 	case 0x10ec0234:
 	case 0x10ec0274: