iio: Rename iio/dds to iio/frequency

Generalize naming to allow other frequency synthesis techniques as well.
No functional changes.

Signed-off-by: Michael Hennerich <michael.hennerich@analog.com>
Acked-by: Jonathan Cameron <jic23@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

drivers/staging/iio/Kconfig

@@ -30,7 +30,7 @@ source "drivers/staging/iio/adc/Kconfig"
 source "drivers/staging/iio/addac/Kconfig"
 source "drivers/staging/iio/cdc/Kconfig"
 source "drivers/staging/iio/dac/Kconfig"
-source "drivers/staging/iio/dds/Kconfig"
+source "drivers/staging/iio/frequency/Kconfig"
 source "drivers/staging/iio/gyro/Kconfig"
 source "drivers/staging/iio/impedance-analyzer/Kconfig"
 source "drivers/staging/iio/imu/Kconfig"

drivers/staging/iio/Makefile

@@ -18,7 +18,7 @@ obj-y += adc/
 obj-y += addac/
 obj-y += cdc/
 obj-y += dac/
-obj-y += dds/
+obj-y += frequency/
 obj-y += gyro/
 obj-y += impedance-analyzer/
 obj-y += imu/