docker-common: remove duplicate set_fact (monitor_name)

this fact is already set in ceph-defaults, there is no need to set it
again in ceph-docker-common

Signed-off-by: Guillaume Abrioux <gabrioux@redhat.com>

roles/ceph-docker-common/tasks/main.yml

@@ -10,19 +10,6 @@
   when:
     - not is_atomic
 
-# NOTE(guits): would be nice to refact this block with L39-45 in roles/ceph-common/tasks/facts.yml
-- name: set_fact monitor_name ansible_hostname
-  set_fact:
-    monitor_name: "{{ ansible_hostname }}"
-  when:
-    - not mon_use_fqdn
-
-- name: set_fact monitor_name ansible_fqdn
-  set_fact:
-    monitor_name: "{{ ansible_fqdn }}"
-  when:
-    - mon_use_fqdn
-
 - name: get docker version
   command: docker --version
   changed_when: false