ASoC: Correct element count for WM8996 sidetone HPF

I can count. Honest.
Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
Acked-by: Liam Girdwood <lrg@ti.com>

sound/soc/codecs/wm8996.c

@@ -420,7 +420,7 @@ static const char *sidetone_hpf_text[] = {
 };
 
 static const struct soc_enum sidetone_hpf =
-	SOC_ENUM_SINGLE(WM8996_SIDETONE, 7, 6, sidetone_hpf_text);
+	SOC_ENUM_SINGLE(WM8996_SIDETONE, 7, 7, sidetone_hpf_text);
 
 static const char *hpf_mode_text[] = {
 	"HiFi", "Custom", "Voice"