qa/suites/rados/mgr/tasks/failover: whitelist

qa/suites/rados/mgr/tasks/failover: whitelist

remote/smithi025/log/ceph.log.gz:2017-08-03 07:02:15.049074 mon.b mon.0 172.21.15.25:6789/0 197 : cluster [INF] Manager daemon x is unresponsive, replacing it with standby daemon y
remote/smithi025/log/ceph.log.gz:2017-08-03 07:03:10.078032 mon.b mon.0 172.21.15.25:6789/0 226 : cluster [WRN] Manager daemon x is unresponsive.  No standby daemons available.

x and y may be swapped, so whitelist the rest of the string.

Signed-off-by: Sage Weil <sage@redhat.com>