staging: iio: imu: allow adis16300 and adis16400 to build without ring buffer support.

Signed-off-by: Jonathan Cameron <jic23@cam.ac.uk>
Acked-by: Barry Song <21cnbao@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
diff --git a/drivers/staging/iio/imu/Kconfig b/drivers/staging/iio/imu/Kconfig
index 48a712e..31a6233 100644
--- a/drivers/staging/iio/imu/Kconfig
+++ b/drivers/staging/iio/imu/Kconfig
@@ -6,9 +6,8 @@
 config ADIS16300
 	tristate "Analog Devices ADIS16300 IMU SPI driver"
 	depends on SPI
-	select IIO_SW_RING
-	select IIO_RING_BUFFER
-	select IIO_TRIGGER
+	select IIO_SW_RING if IIO_RING_BUFFER
+	select IIO_TRIGGER if IIO_RING_BUFFER
 	help
 	  Say yes here to build support for Analog Devices adis16300 four degrees
 	  of freedom inertial sensor.
@@ -25,9 +24,8 @@
 config ADIS16400
 	tristate "Analog Devices ADIS16400/5 IMU SPI driver"
 	depends on SPI
-	select IIO_SW_RING
-	select IIO_RING_BUFFER
-	select IIO_TRIGGER
+	select IIO_SW_RING if IIO_RING_BUFFER
+	select IIO_TRIGGER if IIO_RING_BUFFER
 	help
 	  Say yes here to build support for Analog Devices adis16400/5 triaxial
 	  inertial sensor with Magnetometer.