ceph-mds: do not enable multimds on jewel

Multiple active MDS became stable in Luminous.

Introduced-by: c8573fe0

Signed-off-by: Patrick Donnelly <pdonnell@redhat.com>
(cherry picked from commit 9ce81ae8)

roles/ceph-mon/tasks/create_mds_filesystems.yml

@@ -25,7 +25,7 @@
   command: "{{ docker_exec_cmd }} ceph --cluster {{ cluster }} fs set {{ cephfs }} allow_multimds true --yes-i-really-mean-it"
   changed_when: false
   when:
-    - ceph_release_num.{{ ceph_release }} >= ceph_release_num.jewel
+    - ceph_release_num[ceph_release] == ceph_release_num.luminous
     - mds_allow_multimds
 
 - name: set max_mds