Fix compiler warning.
Fix compiler warning.

Commit 468bf68f18 changes some fields but forgot the initialization.
50wu/gpdb,ashwinstar/gpdb,lisakowen/gpdb,50wu/gpdb,jmcatamney/gpdb,greenplum-db/gpdb,50wu/gpdb,greenplum-db/gpdb,xinzweb/gpdb,50wu/gpdb,lisakowen/gpdb,lisakowen/gpdb,adam8157/gpdb,greenplum-db/gpdb,lisakowen/gpdb,ashwinstar/gpdb,adam8157/gpdb,lisakowen/gpdb,adam8157/gpdb,adam8157/gpdb,xinzweb/gpdb,lisakowen/gpdb,jmcatamney/gpdb,xinzweb/gpdb,50wu/gpdb,xinzweb/gpdb,50wu/gpdb,jmcatamney/gpdb,jmcatamney/gpdb,jmcatamney/gpdb,adam8157/gpdb,ashwinstar/gpdb,greenplum-db/gpdb,ashwinstar/gpdb,greenplum-db/gpdb,xinzweb/gpdb,xinzweb/gpdb,greenplum-db/gpdb,ashwinstar/gpdb,ashwinstar/gpdb,jmcatamney/gpdb,jmcatamney/gpdb,adam8157/gpdb,50wu/gpdb,greenplum-db/gpdb,ashwinstar/gpdb,ashwinstar/gpdb,adam8157/gpdb,jmcatamney/gpdb,xinzweb/gpdb,adam8157/gpdb,greenplum-db/gpdb,lisakowen/gpdb,xinzweb/gpdb,lisakowen/gpdb,50wu/gpdb