message: More explicit define about CAN protocols.

Change a bit CAN binding define about used protocol. There was a mistake
about BCM define which isn't a protocol at all but a maner to filter
and retrieve CAN message through SocketCAN. Also FD_FRAME was using the
same name than SocketCAN which isn't a good idea, better to distinguis both
of them.

Bug-AGL: SPEC-2988

Change-Id: I255fa03029c7d5f90a33448e5e7692d8c249279b
Signed-off-by: Romain Forlot <romain.forlot@iot.bzh>