Staging: IIO: kxsd9 accelerometer minimal support

Staging: IIO: kxsd9 accelerometer minimal support

This provides only very minimal support for this device.
Note that an alternate driver has been posted to the input
mailing list.

When the original LMKL discussion that led to the descision
to develop IIO occured, the question on whether the differing
requirements of IIO and input drivers made it a good idea
to have unified drivers was left as an open question.
It still is.  All opinions on this question welcome.

Signed-off-by: Jonathan Cameron <jic23@cam.ac.uk>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>