pgsql: Query in SQL function still not schema-safe; add a couple more

Log Message:
-----------
Query in SQL function still not schema-safe; add a couple
more pg_catalog. qualifications.

Modified Files:
--------------
pgsql/src/backend/catalog:
information_schema.sql (r1.55 -> r1.56)
(http://anoncvs.postgresql.org/cvsweb.cgi/pgsql/src/backend/catalog/information_schema.sql?r1=1.55&r2=1.56)