ASoC: Set idle_bias_off flag in snd_soc_codec_driver

Since commit 33c5f969 "ASoC: Allow idle_bias_off to be specified in CODEC
drivers", now we can set idle_bias_off flag in struct snd_soc_codec_driver
for devices can unconditionally support idle_bias_off.

Signed-off-by: Axel Lin <axel.lin@gmail.com>
Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
diff --git a/sound/soc/codecs/wm8904.c b/sound/soc/codecs/wm8904.c
index 14afc11..37079ea 100644
--- a/sound/soc/codecs/wm8904.c
+++ b/sound/soc/codecs/wm8904.c
@@ -2088,7 +2088,6 @@
 	int ret, i;
 
 	codec->cache_sync = 1;
-	codec->dapm.idle_bias_off = 1;
 	codec->control_data = wm8904->regmap;
 
 	switch (wm8904->devtype) {
@@ -2237,6 +2236,7 @@
 	.suspend =	wm8904_suspend,
 	.resume =	wm8904_resume,
 	.set_bias_level = wm8904_set_bias_level,
+	.idle_bias_off = true,
 };
 
 static const struct regmap_config wm8904_regmap = {