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>
diff --git a/drivers/staging/iio/Makefile b/drivers/staging/iio/Makefile
index 2acd42f..6a46d5a 100644
--- a/drivers/staging/iio/Makefile
+++ b/drivers/staging/iio/Makefile
@@ -18,7 +18,7 @@
 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/