"Shielded" nodes have a virtual TPM attached which is used for
generating the client certificate, instead of using a bootstrap
kubeconfig. Determining which to use happens during node startup based
on the instance metadata.
Looks like the get-master-root-disk-size() and get-master-disk-size() functions didn't anticipate
clusters bigger than 2K nodes.
In https://github.com/kubernetes/kubernetes/issues/72976 we found out
that 100GB may be not enough for large clusters (5K nodes) when it comes
to master root disk size.
Updating both get-master-root-disk-size() and get-master-disk-size() to
make them consistent and match cluster sizes with get-master-size()
function.
