As well make all the variables assigned in a way that they can be
overwritten so we can give maximum flexibility to distros.
Signed-off-by: Andrei Gherzan <andrei@gherzan.ro>
The latest raspberrypi3 puts its console on ttyS0 instead of ttyAMA0 (like all
the preceding boards). Therefore pull this definition out of the common
include file and add it separately for each MACHINE.
Signed-off-by: Trevor Woerner <twoerner@gmail.com>
