ALSA: hda - Fix Center/LFE mixer element creations for Realtek

The commit 23c09b00
    ALSA: hda - Support multiple speakers by Realtek auto-parser
changes the return value from alc_get_line_out_pfx(), and it breaks
the center/LFE mixer split check.  The caller must test with a string
"CLFE" now.
Signed-off-by: Takashi Iwai <tiwai@suse.de>

sound/pci/hda/patch_realtek.c

@@ -3014,7 +3014,7 @@ static int alc_auto_create_multi_out_ctls(struct hda_codec *codec,
 		sw = alc_look_for_out_mute_nid(codec, pin, dac);
 		vol = alc_look_for_out_vol_nid(codec, pin, dac);
 		name = alc_get_line_out_pfx(spec, i, true, &index);
-		if (!name) {
+		if (!name || !strcmp(name, "CLFE")) {
 			/* Center/LFE */
 			err = alc_auto_add_vol_ctl(codec, "Center", 0, vol, 1);
 			if (err < 0)