Apply attribute to hide main data source topic in keydef tag.
Apply attribute to hide main data source topic in keydef tag.

Use the same audience= attr as the corresponding topicref tag.

Change-Id: I5c7d3bf9a2a2c3fe73873fea95d025d838e987bb
Reviewed-on: http://gerrit.cloudera.org:8080/5592
Reviewed-by: John Russell <308573a947c636ab812b35943b6242633bef8113@cloudera.com>
Tested-by: John Russell <308573a947c636ab812b35943b6242633bef8113@cloudera.com>

cloudera/Impala,cloudera/Impala,cloudera/Impala,cloudera/Impala,cloudera/Impala,michaelhkw/incubator-impala,cloudera/Impala,michaelhkw/incubator-impala,michaelhkw/incubator-impala,michaelhkw/incubator-impala,cloudera/Impala,michaelhkw/incubator-impala,michaelhkw/incubator-impala,michaelhkw/incubator-impala