ASoC: wm8510: remove invalid free of devm_ allocated data

Fixes following warning.
sound/soc/codecs/wm8510.c:614:1-6: WARNING: invalid free of devm_ allocated data
Signed-off-by: Tushar Behera <tushar.behera@linaro.org>
Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>

sound/soc/codecs/wm8510.c

@@ -608,10 +608,7 @@ static int wm8510_probe(struct snd_soc_codec *codec)
 /* power down chip */
 static int wm8510_remove(struct snd_soc_codec *codec)
 {
-	struct wm8510_priv *wm8510 = snd_soc_codec_get_drvdata(codec);
-
 	wm8510_set_bias_level(codec, SND_SOC_BIAS_OFF);
-	kfree(wm8510);
 	return 0;
 }