Peng Xu 1cfde25e40 Local geomagnetic field update to sensor
Local geomagnetic field strength, declination, inclination information
is useful for magnetometer calibration. It also benefits rotation
vector sensor implementation as it gives a baseline that aids detecting
magnetic field disturbance.

Bug: 30958130
Test: Tested with marlin. Modified hal implementation can get local
      geomagnetic field.

Change-Id: I373fe74d5a091a3adb80ff3c61e441edcf5a253b
2017-04-04 12:35:49 -07:00
..
2017-01-12 14:43:41 -08:00