ASoC: tlv320dac33: Fix compillation error

Fix the compilation error introduced by patch:
ASoC: tlv320dac33: Avoid multiple soft power up
Signed-off-by: Peter Ujfalusi <peter.ujfalusi@nokia.com>
Acked-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
Signed-off-by: Liam Girdwood <lrg@slimlogic.co.uk>

sound/soc/codecs/tlv320dac33.c

@@ -646,6 +646,7 @@ static int dac33_add_widgets(struct snd_soc_codec *codec)
 static int dac33_set_bias_level(struct snd_soc_codec *codec,
 				enum snd_soc_bias_level level)
 {
+	struct tlv320dac33_priv *dac33 = snd_soc_codec_get_drvdata(codec);
 	int ret;
 
 	switch (level) {