ASoC: Move bias level update to the core

All drivers have the same line at the end of the set_bias_level callback to
update the bias_level state. Move this update into
snd_soc_dapm_force_bias_level() and remove them from the drivers.

Signed-off-by: Lars-Peter Clausen <lars@metafoo.de>
Signed-off-by: Mark Brown <broonie@kernel.org>
diff --git a/sound/soc/codecs/ssm4567.c b/sound/soc/codecs/ssm4567.c
index a984485..643bcff 100644
--- a/sound/soc/codecs/ssm4567.c
+++ b/sound/soc/codecs/ssm4567.c
@@ -361,12 +361,7 @@
 		break;
 	}
 
-	if (ret)
-		return ret;
-
-	codec->dapm.bias_level = level;
-
-	return 0;
+	return ret;
 }
 
 static const struct snd_soc_dai_ops ssm4567_dai_ops = {