Kernel 4.15 added a new eBPF program that can
be used with cgroup v2 to control & observe device
access (e.g. read, write, mknod) - `BPF_PROG_TYPE_CGROUP_DEVICE`.
We add the ability to create these programs with the `cgroup_device`
proc macro which creates the `cgroup/dev` link section. Device
details are available to the eBPF program in `DeviceContext`.
The userspace representation is provided with the `CgroupDevice`
structure.
Fixes: #212
Signed-off-by: Milan <milan@mdaverde.com>
Milan