Add linaro-us cloud to nodepool

We have enough quota for 44 8-node hosts; give ourselves a little
headroom.  The mirror host is up and responding.

Story: #2007195
Task: #38357
Change-Id: Ib6797c5bcc90d492c4a47e173b93b3867548879f

nodepool/nb03.openstack.org.yaml

@@ -58,6 +58,12 @@ providers:
           hw_disk_bus: scsi
           hw_scsi_model: virtio-scsi
 
+  - name: linaro-us
+    region-name: 'RegionOne'
+    cloud: linaro-us
+    rate: 0.25
+    diskimages: *provider_diskimages
+
 diskimages:
   - name: ubuntu-xenial-arm64
     elements:

nodepool/nl03.openstack.org.yaml

@@ -377,7 +377,7 @@ providers:
     boot-timeout: 600
     launch-timeout: 800
     rate: 0.001
-    diskimages:
+    diskimages: &linaro_provider_diskimages
       - name: debian-buster-arm64
         config-drive: true
       - name: debian-stretch-arm64
@@ -389,7 +389,7 @@ providers:
     pools:
       - name: main
         max-servers: 8
-        labels:
+        labels: &linaro_provider_labels
           - name: debian-buster-arm64
             min-ram: 8000
             flavor-name: 'os.large'
@@ -411,6 +411,18 @@ providers:
             diskimage: ubuntu-bionic-arm64
             key-name: infra-root-keys-2018-06-15
 
+  - name: linaro-us
+    region-name: 'RegionOne'
+    cloud: linaro-us
+    boot-timeout: 600
+    launch-timeout: 800
+    rate: 0.001
+    diskimages: *linaro_provider_diskimages
+    pools:
+      - name: main
+        max-servers: 40
+        labels: *linaro_provider_labels
+
 diskimages:
   - name: centos-7
   - name: centos-8

zuul/site-variables.yaml

@@ -4,7 +4,7 @@
 # new opendev.org based mirrors, but then eventually be removed once
 # all are updated.
 zuul_site_mirror_fqdn: >-
-  {%- if nodepool.region + "." + nodepool.cloud in [ "DFW.rax", "ORD.rax", "regionOne.fortnebula", "mtl01.inap" ] -%}
+  {%- if nodepool.region + "." + nodepool.cloud in [ "DFW.rax", "ORD.rax", "regionOne.fortnebula", "mtl01.inap", "RegionOne.linaro-us" ] -%}
   mirror.{{ nodepool.region | lower }}.{{ nodepool.cloud | lower }}.opendev.org
   {%- else -%}
   mirror.{{ nodepool.region | lower }}.{{ nodepool.cloud | lower }}.openstack.org