node: cpumgr: port to the latest KEP template
node: cpumgr: port to the latest KEP template

This change wants to do as much as mechanical translation
as possible; as consequence, we have now many gaps and TODOs,
which will be filled in followup PR.

Signed-off-by: Francesco Romani <c7100b580e6017ef67482ace46578cdd2d2e0dfe@redhat.com>

kubernetes/enhancements,kubernetes/enhancements,kubernetes/enhancements