Rework of the bitrate setting to allow finer control about the
bit timing settings.
The current settings are propagated via existing netlink
interfaces, reporting the current settings uses custom
ioctls.
Also report bit errors and bus off state if sent from the
device.
Signed-off-by: Christian Gabriel <ch_gabriel@web.de>
If kernel driver version is new enough, report the currently set
bitrates via ioctl.
Kernel will report changed bitrates through special read operations,
send these values to the device.
Signed-off-by: Christian Gabriel <ch_gabriel@web.de>