ALSA: lx6464es: Remove unneeded variable err

This patch fixes below issue reported by coccicheck
sound/pci/lx6464es/lx6464es.c:256:5-8: Unneeded variable: "err". Return
"0" on line 258
Signed-off-by: Hariprasad Kelam <hariprasad.kelam@gmail.com>
Signed-off-by: Takashi Iwai <tiwai@suse.de>

sound/pci/lx6464es/lx6464es.c

@@ -253,9 +253,8 @@ static int lx_pcm_open(struct snd_pcm_substream *substream)
 
 static int lx_pcm_close(struct snd_pcm_substream *substream)
 {
-	int err = 0;
 	dev_dbg(substream->pcm->card->dev, "->lx_pcm_close\n");
-	return err;
+	return 0;
 }
 
 static snd_pcm_uframes_t lx_pcm_stream_pointer(struct snd_pcm_substream