ASoC: fsl_spdif: Fix incorrect usage of regmap_read()

We should not copy the return value into this val since it's supposed to
get the value of the register not the success result of regmap_read().
Thus fix it.
Signed-off-by: Nicolin Chen <Guangyu.Chen@freescale.com>
Signed-off-by: Mark Brown <broonie@linaro.org>

sound/soc/fsl/fsl_spdif.c

@@ -762,7 +762,7 @@ static int fsl_spdif_vbit_get(struct snd_kcontrol *kcontrol,
 	struct regmap *regmap = spdif_priv->regmap;
 	u32 val;
 
-	val = regmap_read(regmap, REG_SPDIF_SIS, &val);
+	regmap_read(regmap, REG_SPDIF_SIS, &val);
 	ucontrol->value.integer.value[0] = (val & INT_VAL_NOGOOD) != 0;
 	regmap_write(regmap, REG_SPDIF_SIC, INT_VAL_NOGOOD);