Add a mutating admission webhook for CCNP

[dongx1x]

What would you like to be added?

Admission webhooks are HTTP callbacks that receive admission requests and do something with them. Mutating admission webhooks can modify objects sent to the API server to enforce custom defaults. It is a common usage in Kubernetes for admission control.

Why is this needed?

With the configfs-tsm merged in the Linux kernel, we don't need such a device plugin to expose the device to CCNP service, and the socket can be added by a mutating admission webhook automatically.

[dongx1x]

A proposal has been submitted to PR #59.