iio: imu: nvi v.336 Add DMP AUX support

iio: imu: nvi v.336 Add DMP AUX support

- Add DMP support for devices on the auxiliary ports behind the MPU/ICM.  Due
  to the differences between the MPU and ICM DMPs, the auxiliary port API was
  extended that allowed the DMP dependencies to be removed from the auxiliary
  device's external drivers.
- Updated the pressure calculations for the BMP280 driver to the latest BMP280
  specification.

Bug 200191681
Bug 200201316
Bug 200195822

Change-Id: Id4338b11094f8ef00df214c14649b7bc951a6891
Signed-off-by: Erik Lilliebjerg <elilliebjerg@nvidia.com>
Reviewed-on: http://git-master/r/1185055
GVS: Gerrit_Virtual_Submit
Tested-by: Robert Collins <rcollins@nvidia.com>
Reviewed-by: Akhilesh Khumbum <akhumbum@nvidia.com>
Reviewed-by: Robert Collins <rcollins@nvidia.com>