Bone can

[lorforlinux]

@jadonk @RobertCNelson please review my code :)
Everything has been tested on BBBWL & BBAI.
The symlinks are not working for CAN (dcan) bus just like they are not working for PWM(ehrpwm) :(

If anyone wants to use the CAN bus with these overlays then, after loading the overlay they can use these commands:

Setting up can interface
$ sudo modprobe can-raw
$ sudo ip link set can0 up type can bitrate 125000
$ sudo ifconfig can0 up

Using can interface
$ candump can0

It doesn't matter which CAN bus you are using, it will always be can0 for the first, can1 for second and so on...