mirrormanager: enable cron script installation

During the datacenter move the cron script installation was disabled for
IAD2. This removes this conditional to be able to update the cron script
again.

Signed-off-by: Adrian Reber <adrian@lisas.de>

roles/mirrormanager/backend/tasks/main.yml

@@ -40,7 +40,7 @@
   copy: src=backend.cron dest=/etc/cron.d/mm2_backend.cron
   tags:
   - config
-  when: env != 'staging' and datacenter != 'iad2'
+  when: env != 'staging'
 
 - name: install backend helper scripts
   copy: src={{ item }} dest=/usr/local/bin/{{ item }} mode=0755