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: Nkbuild test robot <fengguang.wu@intel.com>
Signed-off-by: NVinod Koul <vinod.koul@intel.com>
Signed-off-by: NMark Brown <broonie@kernel.org>