This simplifies the messaging protocol. Messages will now only have
the raw content plus a checksum byte at the end. We will worry about
needs of the transport layer (e.g. preamble/postamble bytes) on the
host driver side, and will not support variable-length commands for
now.
There is also a protocol version command, which is now command number
0x00, which returns a 4-byte protocol version followed by a 1-byte
checksum.
BUG=none
TEST=tested on daisy using mkbp kernel driver
Signed-off-by: David Hendricks <dhendrix@chromium.org>
Change-Id: I8fcc693cd50bc2b515164ea7a2a941cdd8333e73
ef9424dd10