iio: imu: fxos8700: fix failed initialization ODR mode assignment

The absence of correct offset leads a failed initialization ODR mode
assignment.

Select MAX ODR mode as the initialization ODR mode by field mask and
FIELD_PREP.

Fixes: 84e5ddd5 ("iio: imu: Add support for the FXOS8700 IMU")
Signed-off-by: Carlos Song <carlos.song@nxp.com>
Link: https://lore.kernel.org/r/20230118074227.1665098-3-carlos.song@nxp.com


Cc: <Stable@vger.kernel.org>
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>