Revert "Disable airship citylcoud nodepool provider"

This reverts commit fab58f375a.

It is reported that city network has fixed the glance issues and we can
reenable this cloud region.

Change-Id: Id118ac0845063fa0ddf8338f14099393de6cb397

nodepool/nl02.opendev.org.yaml

@@ -201,7 +201,7 @@ providers:
     pools:
       - name: main
         # Canary capacity (by memory less than half capacity of airship pool).
-        max-servers: 0
+        max-servers: 10
         labels:
           - name: centos-7
             min-ram: 8000
@@ -273,7 +273,7 @@ providers:
       - name: airship
         # Jobs expected to run 1x 32GB instance + 3x 16GB instances with
         # goal of running 4 jobs concurrently.
-        max-servers: 0
+        max-servers: 16
         labels:
           - name: ubuntu-bionic-expanded
             min-ram: 16000

nodepool/nodepool.yaml

@@ -98,49 +98,7 @@ providers:
     region-name: 'Kna1'
     cloud: airship-citycloud
     rate: 0.25
-    diskimages:
+    diskimages: *provider_diskimages
-      - name: centos-7
-        config-drive: true
-        pause: true
-      - name: centos-8
-        config-drive: true
-        pause: true
-      - name: centos-8-stream
-        config-drive: true
-        pause: true
-      - name: debian-bullseye
-        config-drive: true
-        pause: true
-      - name: debian-buster
-        config-drive: true
-        pause: true
-      - name: debian-stretch
-        config-drive: true
-        pause: true
-      - name: fedora-32
-        config-drive: true
-        pause: true
-      - name: fedora-34
-        config-drive: true
-        pause: true
-      - name: gentoo-17-0-systemd
-        config-drive: true
-        pause: true
-      - name: opensuse-15
-        config-drive: true
-        pause: true
-      - name: opensuse-tumbleweed
-        config-drive: true
-        pause: true
-      - name: ubuntu-bionic
-        config-drive: true
-        pause: true
-      - name: ubuntu-focal
-        config-drive: true
-        pause: true
-      - name: ubuntu-xenial
-        config-drive: true
-        pause: true
 
   - name: inmotion-iad3
     region-name: 'iad3'