ASoC: Fix spurious codec driver dependencies

Kbuild ignores dependency from things that are themselves selected so
ASoC machine drivers need to ensure that the control bus is being built.
This also avoids issues where multiple buses are supported by a given
codec.

Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
diff --git a/sound/soc/omap/Kconfig b/sound/soc/omap/Kconfig
index ccd8973..675732e 100644
--- a/sound/soc/omap/Kconfig
+++ b/sound/soc/omap/Kconfig
@@ -8,7 +8,7 @@
 
 config SND_OMAP_SOC_N810
 	tristate "SoC Audio support for Nokia N810"
-	depends on SND_OMAP_SOC && MACH_NOKIA_N810
+	depends on SND_OMAP_SOC && MACH_NOKIA_N810 && I2C
 	select SND_OMAP_SOC_MCBSP
 	select OMAP_MUX
 	select SND_SOC_TLV320AIC3X
@@ -17,7 +17,7 @@
 
 config SND_OMAP_SOC_OSK5912
 	tristate "SoC Audio support for omap osk5912"
-	depends on SND_OMAP_SOC && MACH_OMAP_OSK
+	depends on SND_OMAP_SOC && MACH_OMAP_OSK && I2C
 	select SND_OMAP_SOC_MCBSP
 	select SND_SOC_TLV320AIC23
 	help