Staging: IIO: add selection of IIO_SW_RING to LIS3L02DQ as needed

Here I've kept the selection of IIO_SW_RING separate from
IIO_TRIGGER as it will go away fairly shortly when the ring buffer
type becomes configurable on a per device basis, whereas the
IIO_TRIGGER select will remain. Whether to retain the option to
remove the support for ring buffers entirely is one for after that
support is in place.
Reported-by: Randy Dunlap <randy.dunlap@oracle.com>
Signed-off-by: Jonathan Cameron <jic23@cam.ac.uk>
Acked-by: Randy Dunlap <randy.dunlap@oracle.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

drivers/staging/iio/accel/Kconfig

@@ -14,6 +14,7 @@ config LIS3L02DQ
 	tristate "ST Microelectronics LIS3L02DQ Accelerometer Driver"
 	depends on SPI
 	select IIO_TRIGGER if IIO_RING_BUFFER
+	select IIO_SW_RING if IIO_RING_BUFFER
 	help
 	  Say yes here to build SPI support for the ST microelectronics
 	  accelerometer. The driver supplies direct access via sysfs files