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
- uses the FIFO and SPI DMA to transfer full raw data (8 kHz gyro, 4 kHz accel)
- new sensor messages for better visibility
- sensor_{accel, gyro}_fifo: full raw data for optional logging and analysis
- sensor_{accel, gyro}_status: metadata, clipping, etc
- currently not enabled by default
* The build is built with SPI4. At run time the signal GPIO_8266_GPIO2 it tested. If it is low the SPI4 is configured. If it is high SPI4 is not configured.
* board_common: Add Notion of Board has bus manifest
