Add the debugfs framework to the driver and create a debugfs
command interface for each device.

example command:
"echo queue info > cmd" Query the packet forwarding queue information.
Signed-off-by: Nliuzhongzhu <liuzhongzhu@huawei.com>
Signed-off-by: NSalil Mehta <salil.mehta@huawei.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>