ASoC: Fix I2C dependency for SND_FSI_AK4642 and SND_FSI_DA7210

The config option SND_FSI_AK4642 selects SND_SOC_AK4642 which in turn
enables the compilation of ak4642.c - however this codec uses I2C to
communicate with the HW.
Same applies to DA7210.

Consequently when I2C is not set, the compilation fails [1]

This patch fixes this issues, by adding a depencdency on the related HW-
controller.

Signed-off-by: Peter Huewe <peterhuewe@gmx.de>
Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>

sound/soc/sh/Kconfig

@@ -48,15 +48,15 @@ config SND_SH7760_AC97
 
 config SND_FSI_AK4642
 	bool "FSI-AK4642 sound support"
-	depends on SND_SOC_SH4_FSI
+	depends on SND_SOC_SH4_FSI && I2C_SH_MOBILE
 	select SND_SOC_AK4642
 	help
 	  This option enables generic sound support for the
 	  FSI - AK4642 unit
 
 config SND_FSI_DA7210
 	bool "FSI-DA7210 sound support"
-	depends on SND_SOC_SH4_FSI
+	depends on SND_SOC_SH4_FSI && I2C_SH_MOBILE
 	select SND_SOC_DA7210
 	help
 	  This option enables generic sound support for the