Introducing a CNI interface where kubelet can source max IP allocatable for a node

[AbeOwlu]

Similar to the CSINode KEP,

• discussing a standard interface that can be exposed on the VPC CNI, perhaps the CNINode object, which can be used by kubelet to source the max IP that can accurately(dynamically) be attached to a node for pods.

This should optimize, and reduce possible pods over-scheduling issues;