ASoC: Intel: Skylake: Add I2C depends for SKL machine

The i2c is dependency for the i2c codec drivers, so machine should depend on
i2c. WIthout this we get build failures if I2C is not selected

   sound/soc/codecs/rl6347a.c: In function 'rl6347a_hw_write':
>> sound/soc/codecs/rl6347a.c:66:8: error: implicit declaration of function
>> 'i2c_master_send' [-Werror=implicit-function-declaration]
     ret = i2c_master_send(client, data, 4);
           ^
   sound/soc/codecs/rl6347a.c: In function 'rl6347a_hw_read':
>> sound/soc/codecs/rl6347a.c:114:8: error: implicit declaration of function
>> 'i2c_transfer' [-Werror=implicit-function-declaration]
     ret = i2c_transfer(client->adapter, xfer, 2);
Reported-by: kbuild test robot <fengguang.wu@intel.com>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
Signed-off-by: Mark Brown <broonie@kernel.org>

sound/soc/intel/Kconfig

@@ -144,7 +144,7 @@ config SND_SOC_INTEL_SKYLAKE
 
 config SND_SOC_INTEL_SKL_RT286_MACH
 	tristate "ASoC Audio driver for SKL with RT286 I2S mode"
-	depends on X86 && ACPI
+	depends on X86 && ACPI && I2C
 	select SND_SOC_INTEL_SST
 	select SND_SOC_INTEL_SKYLAKE
 	select SND_SOC_RT286