hack/build: Pin to RHCOS 400.7.20190306.0

This is the most recent RHCOS:

  $ curl -s https://releases-rhcos.svc.ci.openshift.org/storage/releases/maipo/builds.json | jq '{"latest": .builds[0], timestamp}'
  {
    "latest": "400.7.20190306.0",
    "timestamp": "2019-03-06T22:24:53Z"
  }

I'd prefer to pull this from the release image:

  $ oc adm release info --pullspecs quay.io/openshift-release-dev/ocp-release:4.0.0-0.7 | grep machine-os-content
    machine-os-content                            quay.io/openshift-release-dev/ocp-v4.0-art-dev@sha256:399582f711226ab1a0e76d8928ec55436dea9f8dc60976c10790d308b9d92181
  $ oc image info quay.io/openshift-release-dev/ocp-v4.0-art-dev@sha256:399582f711226ab1a0e76d8928ec55436dea9f8dc60976c10790d308b9d92181 | grep version
              version=47.330

But [1] isn't green yet, so hard-coding here is a quick fix.

Supported regions:

  $ curl -s https://releases-rhcos.svc.ci.openshift.org/storage/releases/maipo/400.7.20190306.0/meta.json | jq -r '.amis[] | .name'
  ap-northeast-1
  ap-northeast-2
  ap-south-1
  ap-southeast-1
  ap-southeast-2
  ca-central-1
  eu-central-1
  eu-west-1
  eu-west-2
  eu-west-3
  sa-east-1
  us-east-1
  us-east-2
  us-west-1
  us-west-2

[1]: #1286

hack/build.sh

@@ -2,6 +2,8 @@
 
 set -ex
 
+RHCOS_BUILD_NAME="${RHCOS_BUILD_NAME:-400.7.20190306.0}"
+
 # shellcheck disable=SC2068
 version() { IFS="."; printf "%03d%03d%03d\\n" $@; unset IFS;}
 

pkg/types/aws/validation/platform.go

@@ -15,25 +15,25 @@ var (
 	Regions = map[string]string{
 		"ap-northeast-1": "Tokyo",
 		"ap-northeast-2": "Seoul",
-		"ap-northeast-3": "Osaka-Local",
+		//"ap-northeast-3": "Osaka-Local",
 		"ap-south-1":     "Mumbai",
 		"ap-southeast-1": "Singapore",
 		"ap-southeast-2": "Sydney",
 		"ca-central-1":   "Central",
-		"cn-north-1":     "Beijing",
-		"cn-northwest-1": "Ningxia",
-		"eu-central-1":   "Frankfurt",
-		"eu-north-1":     "Stockholm",
-		"eu-west-1":      "Ireland",
-		"eu-west-2":      "London",
-		"eu-west-3":      "Paris",
-		"sa-east-1":      "São Paulo",
-		"us-east-1":      "N. Virginia",
-		"us-east-2":      "Ohio",
-		"us-gov-east-1":  "AWS GovCloud (US-East)",
-		"us-gov-west-1":  "AWS GovCloud (US-West)",
-		"us-west-1":      "N. California",
-		"us-west-2":      "Oregon",
+		//"cn-north-1":     "Beijing",
+		//"cn-northwest-1": "Ningxia",
+		"eu-central-1": "Frankfurt",
+		//"eu-north-1":     "Stockholm",
+		"eu-west-1": "Ireland",
+		"eu-west-2": "London",
+		"eu-west-3": "Paris",
+		"sa-east-1": "São Paulo",
+		"us-east-1": "N. Virginia",
+		"us-east-2": "Ohio",
+		//"us-gov-east-1":  "AWS GovCloud (US-East)",
+		//"us-gov-west-1":  "AWS GovCloud (US-West)",
+		"us-west-1": "N. California",
+		"us-west-2": "Oregon",
 	}
 
 	validRegionValues = func() []string {

pkg/types/validation/installconfig_test.go

@@ -370,7 +370,7 @@ func TestValidateInstallConfig(t *testing.T) {
 				}
 				return c
 			}(),
-			expectedError: `^platform\.aws\.region: Unsupported value: "": supported values: "ap-northeast-1", "ap-northeast-2", "ap-northeast-3", "ap-south-1", "ap-southeast-1", "ap-southeast-2", "ca-central-1", "cn-north-1", "cn-northwest-1", "eu-central-1", "eu-north-1", "eu-west-1", "eu-west-2", "eu-west-3", "sa-east-1", "us-east-1", "us-east-2", "us-gov-east-1", "us-gov-west-1", "us-west-1", "us-west-2"$`,
+			expectedError: `^platform\.aws\.region: Unsupported value: "": supported values: "ap-northeast-1", "ap-northeast-2", "ap-south-1", "ap-southeast-1", "ap-southeast-2", "ca-central-1", "eu-central-1", "eu-west-1", "eu-west-2", "eu-west-3", "sa-east-1", "us-east-1", "us-east-2", "us-west-1", "us-west-2"$`,
 		},
 		{
 			name: "valid libvirt platform",