GMIN-3015: Refine a little bit the magnetometer accuracy indicator
GMIN-3015: Refine a little bit the magnetometer accuracy indicator

We now start at the default (unreliable) level then increase as we
go through calibration stages.

Issue: GMIN-3015

Change-Id: I3432feaad3426748b991da94bc41983d0b97943d
Signed-off-by: Patrick Porlan <6b7a5b9114e07d350ffba0c179039885a7e82794@intel.com>

01org/android-iio-sensors-hal,01org/android-iio-sensors-hal