k/build/debian-* on GCB

cloudbuild.yaml

steps:
- name:    gcr.io/cloud-builders/git
  dir:     go/src/k8s.io/
  args:
  - clone
  - "${_K8S_GIT_URL}"
  - --branch
  - "${_K8S_GIT_BRANCH}"
  waitFor: [ '-' ]
  id:      clone

- name:    gcr.io/cloud-builders/docker
  args:    [ 'pull', "${_BUILDER_IMAGE}" ]
  waitFor: [ '-' ]
  id:      pull-builder

- name:    "${_BUILDER_IMAGE}"
  dir:     "go/src/k8s.io/kubernetes/build/${_IMAGE}"
  args:    [ 'make', 'ARCH=something', 'register-multiarch' ]
  id:      multiarch-register

- &build
  name:    "${_BUILDER_IMAGE}"
  dir:     "go/src/k8s.io/kubernetes/build/${_IMAGE}"
  args:    [ 'make', 'SKIP_REGISTER_MULTIARCH=1', 'build' ]
  waitFor: [ 'multiarch-register' ]
  env:     [ 'ARCH=amd64' ]
  id:      amd64
- <<: *build
  env:     [ 'ARCH=arm' ]
  id:      arm
- <<: *build
  env:     [ 'ARCH=arm64' ]
  id:      arm64
- <<: *build
  env:     [ 'ARCH=ppc64le' ]
  id:      ppc64le
- <<: *build
  env:     [ 'ARCH=s390x' ]
  id:      s390x

- name:    gcr.io/cloud-builders/docker
  args:    [ 'image', 'ls' ]
  id:      inspect

timeout: 6000s

substitutions:
  _K8S_GIT_URL:    https://github.com/kubernetes/kubernetes
  _K8S_GIT_BRANCH: master
  _IMAGE:          debian-hyperkube-base
  _BUILDER_IMAGE:  gcr.io/k8s-staging-release-test/k8s-cloud-builder

Needs kubernetes/kubernetes#80909 to merge.