Splitting OS_DISTRIBUTION into NODE_OS_DISTRIBUTION and

MASTER_OS_DISTRIBUTION.

hack/verify-flags/exceptions.txt

@@ -13,7 +13,7 @@ cluster/gce/configure-vm.sh:  api_servers: '${KUBERNETES_MASTER_NAME}'
 cluster/gce/configure-vm.sh:  cloud_config: ${CLOUD_CONFIG}
 cluster/gce/configure-vm.sh:  env-to-grains "runtime_config"
 cluster/gce/configure-vm.sh:  kubelet_api_servers: '${KUBELET_APISERVER}'
-cluster/gce/coreos/helper.sh:# cloud_config yaml file should be passed
+cluster/gce/coreos/node-helper.sh:# cloud_config yaml file should be passed
 cluster/gce/gci/configure-helper.sh:      reconcile_cidr="false"
 cluster/gce/gci/configure-helper.sh:  local api_servers="--master=https://${KUBERNETES_MASTER_NAME}"
 cluster/gce/gci/configure-helper.sh:  local reconcile_cidr="true"

hack/verify-flags/known-flags.txt

@@ -280,6 +280,7 @@ make-symlinks
 manifest-url
 manifest-url-header
 masquerade-all
+master-os-distro
 master-service-namespace
 max-concurrency
 max-connection-bytes-per-sec
@@ -327,6 +328,7 @@ node-labels
 node-monitor-grace-period
 node-monitor-period
 node-name
+node-os-distro
 node-startup-grace-period
 node-status-update-frequency
 node-sync-period
@@ -339,7 +341,6 @@ oidc-issuer-url
 oidc-username-claim
 only-idl
 oom-score-adj
-os-distro
 out-version
 outofdisk-transition-frequency
 output-base