* Update Kubernetes to v1.21.0
* Update to golang v1.16.2
* Update dependent modules to track with upstream
* Switch to upstream flannel
* Track changes to upstream cloud-controller-manager and FeatureGates
Signed-off-by: Brad Davidson <brad.davidson@rancher.com>
Because:
- Current CNI plugins produces an error on Raspbian:
`failed to create bridge \"cni0\": could not add \"cni0\": operation not supported"`
- Dependencies for CNI plugins may interfere with containerd dependencies.
This change will compile and download CNI plugins separately, and will
downgrade CNI plugins to v0.7.6 for compatability with armv7.