ASoC: wm8900: Cleanup manual bias level transitions

Since the ASoC core now takes care of setting the bias level to
SND_SOC_BIAS_OFF when removing the CODEC there is no need to do it manually
anymore either.
Signed-off-by: Lars-Peter Clausen <lars@metafoo.de>
Acked-by: Charles Keepax <ckeepax@opensource.wolfsonmicro.com>
Signed-off-by: Mark Brown <broonie@kernel.org>

sound/soc/codecs/wm8900.c

@@ -1209,16 +1209,8 @@ static int wm8900_probe(struct snd_soc_codec *codec)
 	return 0;
 }
 
-/* power down chip */
-static int wm8900_remove(struct snd_soc_codec *codec)
-{
-	wm8900_set_bias_level(codec, SND_SOC_BIAS_OFF);
-	return 0;
-}
-
 static struct snd_soc_codec_driver soc_codec_dev_wm8900 = {
 	.probe =	wm8900_probe,
-	.remove =	wm8900_remove,
 	.suspend =	wm8900_suspend,
 	.resume =	wm8900_resume,
 	.set_bias_level = wm8900_set_bias_level,