High: PE: Allow the cluster to make progress by not retrying failed demote actions
Staying in role=master ends up putting the PE/TE into an endless loop
where we keep trying to demote the resource which will keep failing.
Setting role=slave is not dangerous because no master will be promoted
until the failed resource has been fully stopped

Mercurial revision: 60396137c71077d3a1b808344e91b90b413dbf26