Retire linaro-cn1

The SSL cert for the API has expired, so we haven't been talking to
this cloud for some time.  We have been requested to decommission it
[1]; so remove from nodepool config.

Story: #2005353
Task: #30335

[1] http://eavesdrop.openstack.org/irclogs/%23openstack-infra/%23openstack-infra.2019-04-03.log.html#t2019-04-03T22:16:31

Change-Id: I149e74ff5e788bb860deb4c3cc38d9c8ed5766c6

nodepool/nb03.openstack.org.yaml

@@ -18,9 +18,9 @@ labels:
     max-ready-age: 3600
 
 providers:
-  - name: linaro-cn1
-    region-name: 'RegionOne'
-    cloud: linaro
+  - name: linaro-london
+    region-name: 'London'
+    cloud: linaro-london
     rate: 0.25
     diskimages: &provider_diskimages
       - name: ubuntu-xenial-arm64
@@ -48,12 +48,6 @@ providers:
           hw_disk_bus: scsi
           hw_scsi_model: virtio-scsi
 
-  - name: linaro-london
-    region-name: 'London'
-    cloud: linaro-london
-    rate: 0.25
-    diskimages: *provider_diskimages
-
   - name: arm64ci-nrt1
     region-name: 'nrt1'
     cloud: arm64ci

nodepool/nl03.openstack.org.yaml

@@ -341,39 +341,6 @@ providers:
             diskimage: ubuntu-xenial
             key-name: infra-root-keys-2018-06-15
 
-  - name: linaro-cn1
-    region-name: 'RegionOne'
-    cloud: linaro
-    boot-timeout: 600
-    launch-timeout: 800
-    rate: 0.001
-    diskimages:
-      - name: debian-stretch-arm64
-        config-drive: true
-      - name: ubuntu-xenial-arm64
-        config-drive: true
-      - name: ubuntu-bionic-arm64
-        config-drive: true
-    pools:
-      - name: main
-        max-servers: 8
-        labels:
-          - name: debian-stretch-arm64
-            min-ram: 8000
-            flavor-name: 'os.large'
-            diskimage: debian-stretch-arm64
-            key-name: infra-root-keys-2018-06-15
-          - name: ubuntu-xenial-arm64
-            min-ram: 8000
-            flavor-name: 'os.large'
-            diskimage: ubuntu-xenial-arm64
-            key-name: infra-root-keys-2018-06-15
-          - name: ubuntu-bionic-arm64
-            min-ram: 8000
-            flavor-name: 'os.large'
-            diskimage: ubuntu-bionic-arm64
-            key-name: infra-root-keys-2018-06-15
-
   - name: linaro-london
     region-name: 'London'
     cloud: linaro-london