ASoC: Add separate AVDD for WM8400

There is an AVDD supply as well, normally one or more of the other
upplies would be tied to it.

Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
diff --git a/sound/soc/codecs/wm8400.c b/sound/soc/codecs/wm8400.c
index 462f8b0..b7350c2 100644
--- a/sound/soc/codecs/wm8400.c
+++ b/sound/soc/codecs/wm8400.c
@@ -49,6 +49,9 @@
 		.supply = "DCVDD",
 	},
 	{
+		.supply = "AVDD",
+	},
+	{
 		.supply = "FLLVDD",
 	},
 	{