Instead of verifying the CRC before every access of the boot data,
verify the CRC once at startup and set a flag to indicate the boot
data is valid.
Also add a framework to support multiple boot protocol versions.
Firmware declares the maximum supported protocol version using a
version byte in the boot data header. The bootloader chooses the
highest version supported by it and the firmware when deciding
what boot protocol to use.
Change-Id: I810194625dc0833f026d2a23b8d64ed467fa6aca
Bootdata is a special location in the Firmware marked by a magic header
The bootloader is able to copy information to the firmware by locating
this struct and passing data to the firmware when it is loaded but
before it is actually executed
Data is verified by a crc of the bootdata
Change-Id: Ib3d78cc0c3a9d47d6fe73be4747a11b7ad6f0a9e
