ASoC: adau17x1: 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.

Signed-off-by: Lars-Peter Clausen <lars@metafoo.de>
Signed-off-by: Mark Brown <broonie@kernel.org>
diff --git a/sound/soc/codecs/adau1761.c b/sound/soc/codecs/adau1761.c
index 848cab8..5518ebd 100644
--- a/sound/soc/codecs/adau1761.c
+++ b/sound/soc/codecs/adau1761.c
@@ -714,9 +714,9 @@
 
 static const struct snd_soc_codec_driver adau1761_codec_driver = {
 	.probe = adau1761_codec_probe,
-	.suspend = adau17x1_suspend,
 	.resume	= adau17x1_resume,
 	.set_bias_level	= adau1761_set_bias_level,
+	.suspend_bias_off = true,
 
 	.controls = adau1761_controls,
 	.num_controls = ARRAY_SIZE(adau1761_controls),