See the following commit for more information about the
--external-cloud-volume-plugin flag:
https://github.com/kubernetes/kubernetes/pull/52371/commits/070a7b58237ad12582b3b2eff00877e48324ad66

We need this flag for EXTERNAL_CLOUD_PROVIDER flag to work properly with
volume plugins

Also add --provider-id defaulting to hostname as we seem to pick
up the ip address otherwise causing problem with looking up the
node in the cloud provider