ALSA: hda - silence uninitialized variable warning in activate_amp_in()

If snd_hda_get_conn_list() fails then "conn" isn't initialized.
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Takashi Iwai <tiwai@suse.de>

sound/pci/hda/hda_generic.c

@@ -795,6 +795,8 @@ static void activate_amp_in(struct hda_codec *codec, struct nid_path *path,
 	hda_nid_t nid = path->path[i];
 
 	nums = snd_hda_get_conn_list(codec, nid, &conn);
+	if (nums < 0)
+		return;
 	type = get_wcaps_type(get_wcaps(codec, nid));
 	if (type == AC_WID_PIN ||
 	    (type == AC_WID_AUD_IN && codec->single_adc_amp)) {