pgsql: Fix various hash function uses

Fix various hash function uses

These instances were using Datum-returning functions where a
lower-level function returning uint32 would be more appropriate.

Reviewed-by: Tom Lane <tgl@sss.pgh.pa.us>
Discussion: https://www.postgresql.org/message-id/flat/8246d7ff-f4b7-4363-913e-827dadfeb145%40eisentraut.org

Branch
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master

Details
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https://git.postgresql.org/pg/commitdiff/2ad6e80de9a6300daffcc0987667e45012fbecde

Modified Files
--------------
contrib/sepgsql/uavc.c                  | 4 ++--
src/backend/access/common/tupdesc.c     | 6 +++---
src/backend/storage/file/fileset.c      | 2 +-
src/backend/utils/adt/multirangetypes.c | 2 +-
src/backend/utils/adt/rangetypes.c      | 2 +-
src/backend/utils/cache/catcache.c      | 2 +-
6 files changed, 9 insertions(+), 9 deletions(-)