Fix permissions check on pg_stat_get_wal_senders

When Who What
2018-01-06 11:50:44 Simon Riggs (simon) Closed in commitfest 2018-01 with status: Committed
2018-01-05 14:19:58 Simon Riggs (simon) Added simon as committer
2017-12-23 10:56:35 Michael Paquier (michael-kun) New status: Ready for Committer
2017-12-22 06:33:56 Michael Paquier (michael-kun) Changed reviewers to Michael Paquier (michael-kun)
2017-12-22 06:33:48 Michael Paquier (michael-kun) New status: Waiting on Author
2017-12-21 10:32:41 Feike Steenbergen (feike) Changed authors to Feike Steenbergen (feike)
2017-12-21 10:32:32 Feike Steenbergen (feike) Attached mail thread CAK_s-G0c3fXQ_Rpyvj5gHiKnaa9_H1eS+2Oopqm1eOK79V+FKw@mail.gmail.com
2017-12-21 10:32:31 Feike Steenbergen (feike) Created patch record