Description : This function writes the 128 bit SPI lock customer key. The
customer key written using this function can be used with the
spiunlock tool to unlock the SPI port if the SPI port had been
previously locked (see bccmdSpiLockInitiateLock). Therefore, the
customer key should be set before the SPI port is locked. Use
bccmdGetSpiLockStatus to check the SPI Lock status.
<p>Note that the customer key can be incorporated into the
firmware image loaded to flash memory. In this case, it is not
necessary to set the key using this function.