ASoC: Convert WM8994 MICBIASes to supply widgets

There are some in tree systems using the driver but none use the MICBIAS
widgets.
Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>

sound/soc/codecs/wm_hubs.c

@@ -610,8 +610,8 @@ SND_SOC_DAPM_INPUT("IN1RP"),
 SND_SOC_DAPM_INPUT("IN2RN"),
 SND_SOC_DAPM_INPUT("IN2RP:VXRP"),
 
-SND_SOC_DAPM_MICBIAS("MICBIAS2", WM8993_POWER_MANAGEMENT_1, 5, 0),
-SND_SOC_DAPM_MICBIAS("MICBIAS1", WM8993_POWER_MANAGEMENT_1, 4, 0),
+SND_SOC_DAPM_SUPPLY("MICBIAS2", WM8993_POWER_MANAGEMENT_1, 5, 0, NULL, 0),
+SND_SOC_DAPM_SUPPLY("MICBIAS1", WM8993_POWER_MANAGEMENT_1, 4, 0, NULL, 0),
 
 SND_SOC_DAPM_MIXER("IN1L PGA", WM8993_POWER_MANAGEMENT_2, 6, 0,
 		   in1l_pga, ARRAY_SIZE(in1l_pga)),