Removes the calibration on startup, as these values were overwritten by
the system calibration values anyway.
So the only difference is that if all calibration scales were equal to 1,
the driver startup would have failed.
* 8 kHz gyro, 4 kHz accel
* DLPF disabled
* scheduled using data ready interrupts
* FIFO is emptied at 1 kHz by default, but can adjusted via IMU_GYRO_RATEMAX from 250 Hz - 2000 kHz.
* On both px4_fmu-v4 and px4_fmu-v4pro the secondary IMU is an mpu9250 with the same driver
