Fix comment in indexing.c

578b2297, that removed support for WITH OIDS, has changed
CatalogTupleInsert() to not return an Oid, but one comment was still
mentioning that.

Author: Vik Fearing
Discussion: https://postgr.es/m/fef01975-ed10-3601-7b9e-80ecef72d00b@postgresfriends.org

src/backend/catalog/indexing.c

@@ -210,7 +210,6 @@ CatalogTupleCheckConstraints(Relation heapRel, HeapTuple tup)
  * CatalogTupleInsert - do heap and indexing work for a new catalog tuple
  *
  * Insert the tuple data in "tup" into the specified catalog relation.
- * The Oid of the inserted tuple is returned.
  *
  * This is a convenience routine for the common case of inserting a single
  * tuple in a system catalog; it inserts a new heap tuple, keeping indexes