ASoC: wm8737: Cleanup manual bias level transitions

Set the CODEC driver's suspend_bias_off flag rather than manually going to
SND_SOC_BIAS_OFF in suspend and SND_SOC_BIAS_STANDBY in resume. This makes
the code a bit shorter and cleaner.

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/wm8737.c

@@ -537,23 +537,6 @@ static struct snd_soc_dai_driver wm8737_dai = {
 	.ops = &wm8737_dai_ops,
 };
 
-#ifdef CONFIG_PM
-static int wm8737_suspend(struct snd_soc_codec *codec)
-{
-	wm8737_set_bias_level(codec, SND_SOC_BIAS_OFF);
-	return 0;
-}
-
-static int wm8737_resume(struct snd_soc_codec *codec)
-{
-	wm8737_set_bias_level(codec, SND_SOC_BIAS_STANDBY);
-	return 0;
-}
-#else
-#define wm8737_suspend NULL
-#define wm8737_resume NULL
-#endif
-
 static int wm8737_probe(struct snd_soc_codec *codec)
 {
 	struct wm8737_priv *wm8737 = snd_soc_codec_get_drvdata(codec);
@@ -590,18 +573,10 @@ static int wm8737_probe(struct snd_soc_codec *codec)
 	return ret;
 }
 
-static int wm8737_remove(struct snd_soc_codec *codec)
-{
-	wm8737_set_bias_level(codec, SND_SOC_BIAS_OFF);
-	return 0;
-}
-
 static struct snd_soc_codec_driver soc_codec_dev_wm8737 = {
 	.probe		= wm8737_probe,
-	.remove		= wm8737_remove,
-	.suspend	= wm8737_suspend,
-	.resume		= wm8737_resume,
 	.set_bias_level = wm8737_set_bias_level,
+	.suspend_bias_off = true,
 
 	.controls = wm8737_snd_controls,
 	.num_controls = ARRAY_SIZE(wm8737_snd_controls),