iio:bma180: Fix scale factors to report correct acceleration units

The userspace interface for acceleration sensors is documented as using
m/s^2 units [Documentation/ABI/testing/sysfs-bus-iio]

The fullscale raw values for the BMA80 corresponds to -/+ 1, 1.5, 2, etc G
depending on the selected mode.

The scale table was converting to G rather than m/s^2.
Change the scaling table to match the documented interface.

See commit 71702e6e, iio: mma8452: Use correct acceleration units,
for a related fix.

Signed-off-by: Peter Meerwald <pmeerw@pmeerw.net>
Cc: Oleksandr Kravchenko <o.v.kravchenko@globallogic.com>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>
Cc: Stable@vger.kernel.org