ASoC: wm8961: Replace direct snd_soc_codec dapm field access

The dapm field of the snd_soc_codec struct is eventually going to be
removed, in preparation for this replace all manual access to
codec->dapm.bias_level with snd_soc_codec_get_bias_level().

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/wm8961.c

@@ -758,7 +758,7 @@ static int wm8961_set_bias_level(struct snd_soc_codec *codec,
 		break;
 
 	case SND_SOC_BIAS_PREPARE:
-		if (codec->dapm.bias_level == SND_SOC_BIAS_STANDBY) {
+		if (snd_soc_codec_get_bias_level(codec) == SND_SOC_BIAS_STANDBY) {
 			/* Enable bias generation */
 			reg = snd_soc_read(codec, WM8961_ANTI_POP);
 			reg |= WM8961_BUFIOEN | WM8961_BUFDCOPEN;
@@ -773,7 +773,7 @@ static int wm8961_set_bias_level(struct snd_soc_codec *codec,
 		break;
 
 	case SND_SOC_BIAS_STANDBY:
-		if (codec->dapm.bias_level == SND_SOC_BIAS_PREPARE) {
+		if (snd_soc_codec_get_bias_level(codec) == SND_SOC_BIAS_PREPARE) {
 			/* VREF off */
 			reg = snd_soc_read(codec, WM8961_PWR_MGMT_1);
 			reg &= ~WM8961_VREF;