iio: frequency: CF_AXI_DDS depends on ADI_AXI_DATA_OFFLOAD

The drivers depends on the following methods:

- axi_data_offload_ctrl_bypass
- axi_data_offload_ctrl_oneshot
- devm_axi_data_offload_get_optional

If optional, a proper ops interface needs to be added.

Signed-off-by: Jorge Marques <jorge.marques@analog.com>

Author: gastmaier

drivers/iio/frequency/Kconfig

@@ -108,6 +108,7 @@ config CF_AXI_DDS
 	tristate "Analog Devices CoreFPGA AXI DDS driver"
 	depends on SPI
 	depends on COMMON_CLK
+	depends on ADI_AXI_DATA_OFFLOAD
 	select IIO_BUFFER_DMAENGINE
 	help
 	  Say yes here to build support for Analog Devices DDS chip