SOLR-5859: add OCP.getCollectionStatus() param description for 'clusterState' to stop 'ant precommit' bitching 'Javadoc: Description expected after this reference' and failing the build

git-svn-id: https://svn.apache.org/repos/asf/lucene/dev/trunk@1584108 13f79535-47bb-0310-9956-ffa450edef68