ASoC: adau1373: Use SOC_ENUM_SINGLE_DECL()

Just replace with the helper macro.  No functional change at all.
Signed-off-by: Takashi Iwai <tiwai@suse.de>
Acked-by: Liam Girdwood <liam.r.girdwood@linux.intel.com>
Acked-by: Lars-Peter Clausen <lars@metafoo.de>
Signed-off-by: Mark Brown <broonie@linaro.org>

sound/soc/codecs/adau1373.c

@@ -576,8 +576,8 @@ static const char *adau1373_decimator_text[] = {
 	"DMIC1",
 };
 
-static const struct soc_enum adau1373_decimator_enum =
-	SOC_ENUM_SINGLE(0, 0, 2, adau1373_decimator_text);
+static SOC_ENUM_SINGLE_DECL(adau1373_decimator_enum,
+			    0, 0, adau1373_decimator_text);
 
 static const struct snd_kcontrol_new adau1373_decimator_mux =
 	SOC_DAPM_ENUM_VIRT("Decimator Mux", adau1373_decimator_enum);