ASoC: wm8990: Use supplies to manage input power

Instead of using a fake register use a supply widget to manage the power
for the inputs, this is more idiomatic and supports regmap conversion.

Signed-off-by: Mark Brown <broonie@linaro.org>
Acked-by: Charles Keepax <ckeepax@opensource.wolfsonmicro.com>

sound/soc/codecs/wm8990.h

@@ -78,7 +78,6 @@
 #define WM8990_PLL1                             0x3C
 #define WM8990_PLL2                             0x3D
 #define WM8990_PLL3                             0x3E
-#define WM8990_INTDRIVBITS			0x3F
 
 #define WM8990_EXT_ACCESS_ENA			0x75
 #define WM8990_EXT_CTL1				0x7a
@@ -818,14 +817,6 @@
  */
 #define WM8990_PLLK2_MASK                       0x00FF  /* PLLK2 - [7:0] */
 
-/*
- * R63 (0x3F) - Internal Driver Bits
- */
-#define WM8990_INMIXL_PWR_BIT			0
-#define WM8990_AINLMUX_PWR_BIT			1
-#define WM8990_INMIXR_PWR_BIT			2
-#define WM8990_AINRMUX_PWR_BIT			3
-
 #define WM8990_MCLK_DIV 0
 #define WM8990_DACCLK_DIV 1
 #define WM8990_ADCCLK_DIV 2