ASoC: rt5651: 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>
Signed-off-by: Mark Brown <broonie@kernel.org>

sound/soc/codecs/rt5651.c

@@ -1571,7 +1571,7 @@ static int rt5651_set_bias_level(struct snd_soc_codec *codec,
 {
 	switch (level) {
 	case SND_SOC_BIAS_PREPARE:
-		if (SND_SOC_BIAS_STANDBY == codec->dapm.bias_level) {
+		if (SND_SOC_BIAS_STANDBY == snd_soc_codec_get_bias_level(codec)) {
 			snd_soc_update_bits(codec, RT5651_PWR_ANLG1,
 				RT5651_PWR_VREF1 | RT5651_PWR_MB |
 				RT5651_PWR_BG | RT5651_PWR_VREF2,