cpluspluscheck: Update include path
cpluspluscheck: Update include path

Some things in src/include/fe_utils require libpq headers, so add
libpq's include path to the command line used here.

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