Fix inconsistent argument naming.
Fix inconsistent argument naming.

Typo in commit 842cb9fa6.

adam8157/gpdb,lisakowen/gpdb,50wu/gpdb,lisakowen/gpdb,greenplum-db/gpdb,xinzweb/gpdb,greenplum-db/gpdb,xinzweb/gpdb,50wu/gpdb,xinzweb/gpdb,xinzweb/gpdb,adam8157/gpdb,greenplum-db/gpdb,xinzweb/gpdb,adam8157/gpdb,lisakowen/gpdb,adam8157/gpdb,greenplum-db/gpdb,50wu/gpdb,xinzweb/gpdb,50wu/gpdb,lisakowen/gpdb,xinzweb/gpdb,greenplum-db/gpdb,50wu/gpdb,adam8157/gpdb,adam8157/gpdb,lisakowen/gpdb,greenplum-db/gpdb,50wu/gpdb,lisakowen/gpdb,greenplum-db/gpdb,greenplum-db/gpdb,lisakowen/gpdb,50wu/gpdb,adam8157/gpdb,adam8157/gpdb,50wu/gpdb,xinzweb/gpdb,lisakowen/gpdb