rolling_update: do not fail the playbook if nfs-ganesha is not present
rolling_update: do not fail the playbook if nfs-ganesha is not present

The rolling update playbook was attempting to stop the
nfs-ganesha service on nodes where jewel is still installed.
The nfs-ganesha service did not exist in jewel so the task fails.

Signed-off-by: Andrew Schoen <1bb641dc23c3a93cce4eee683bcf4b2bea7903a3@redhat.com>

ceph/ceph-ansible,travmi/ceph-ansible,ceph/ceph-ansible,travmi/ceph-ansible,font/ceph-ansible,font/ceph-ansible,fgal/ceph-ansible,fgal/ceph-ansible