ASoC: wm9090: Replace w->codec snd_soc_dapm_to_codec(w->dapm)

The codec field of the snd_soc_widget struct is eventually going to be
removed, use snd_soc_dapm_to_codec(w->dapm) instead.
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/wm9090.c

@@ -254,7 +254,7 @@ SOC_SINGLE_TLV("MIXOUTR IN2B Volume", WM9090_OUTPUT_MIXER4, 0, 3, 1,
 static int hp_ev(struct snd_soc_dapm_widget *w,
 		 struct snd_kcontrol *kcontrol, int event)
 {
-	struct snd_soc_codec *codec = w->codec;
+	struct snd_soc_codec *codec = snd_soc_dapm_to_codec(w->dapm);
 	unsigned int reg = snd_soc_read(codec, WM9090_ANALOGUE_HP_0);
 
 	switch (event) {