Change owner from oid to int4 type.

contrib/findoidjoins/README

contrib/findoidjoins/findoidjoins.c

src/backend/catalog/aclchk.c

src/backend/commands/dbcommands.c

src/backend/storage/smgr/md.c

src/backend/utils/cache/lsyscache.c

src/backend/utils/cache/relcache.c

src/backend/utils/init/miscinit.c

src/backend/utils/init/postinit.c

src/backend/utils/misc/database.c

src/include/catalog/pg_aggregate.h

src/include/catalog/pg_am.h

src/include/catalog/pg_attribute.h

src/include/catalog/pg_attribute_mb.h

src/include/catalog/pg_class.h

src/include/catalog/pg_class_mb.h

src/include/catalog/pg_operator.h

src/include/catalog/pg_proc.h

src/include/catalog/pg_type.h

src/include/miscadmin.h