iio: bmg160: IIO_BUFFER and IIO_TRIGGERED_BUFFER are required

commit 06d2f6ca upstream.

This patch adds selects for IIO_BUFFER and IIO_TRIGGERED_BUFFER. Without
IIO_BUFFER, the driver does not compile.
Signed-off-by: Markus Pargmann <mpa@pengutronix.de>
Reviewed-by: Srinivas Pandruvada <srinivas.pandruvada@linux.intel.com>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>
Signed-off-by: Kamal Mostafa <kamal@canonical.com>

drivers/iio/gyro/Kconfig

@@ -53,7 +53,8 @@ config ADXRS450
 config BMG160
 	tristate "BOSCH BMG160 Gyro Sensor"
 	depends on I2C
-	select IIO_TRIGGERED_BUFFER if IIO_BUFFER
+	select IIO_BUFFER
+	select IIO_TRIGGERED_BUFFER
 	help
 	  Say yes here to build support for Bosch BMG160 Tri-axis Gyro Sensor
 	  driver. This driver also supports BMI055 gyroscope.