ASoC: tas571x: 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: Kevin Cernekee <cernekee@chromium.org>
Signed-off-by: Mark Brown <broonie@kernel.org>

sound/soc/codecs/tas571x.c

@@ -179,7 +179,7 @@ static int tas571x_set_bias_level(struct snd_soc_codec *codec,
 	case SND_SOC_BIAS_PREPARE:
 		break;
 	case SND_SOC_BIAS_STANDBY:
-		if (codec->dapm.bias_level == SND_SOC_BIAS_OFF) {
+		if (snd_soc_codec_get_bias_level(codec) == SND_SOC_BIAS_OFF) {
 			if (!IS_ERR(priv->mclk)) {
 				ret = clk_prepare_enable(priv->mclk);
 				if (ret) {