AP_InertialSensor_MPU9250: Add missing library for example/

In order to compile the examples test a library needed to
added.
Tools: Add PXF enable and check CS scripts
AP_Baro_MS5611_test: Remove CS from example code

The CS should be handled automatically by the SPIDriver.
Instead, it can also be controlled with the scripts
created for this purpose and available at Tools/PXF/.
MPU9150: Add missing library to test example.
SPIDriver: Add CS capabilities to the driver.
AP_InertialSensor_MPU9250: Fix SPI CS.
AP_InertialSensor_MPU6000: Fix the CS.
AP_InertialSensor_LSM9DS0: Fix the CS.
config.h: adapt it to PXF and Erle's hardware.

The config.h file is modified
according to the sensors included at the
PixHawk Fire Cape and Erle Robot.