iio: Fix mag3110 Kconfig dependencies

Signed-off-by: NPeter Meerwald <pmeerw@pmeerw.net>
Signed-off-by: NJonathan Cameron <jic23@kernel.org>

drivers/iio/magnetometer/Kconfig

@@ -19,6 +19,8 @@ config AK8975
 config MAG3110
 	tristate "Freescale MAG3110 3-Axis Magnetometer"
 	depends on I2C
+	select IIO_BUFFER
+	select IIO_TRIGGERED_BUFFER
 	help
 	  Say yes here to build support for the Freescale MAG3110 3-Axis
 	  magnetometer.