pgsql: Remove support for unlogged on partitioned tables

Remove support for unlogged on partitioned tables

The following commands were allowed on partitioned tables, with
different effects:
1) ALTER TABLE SET [UN]LOGGED did not issue an error, and did not update
pg_class.relpersistence.
2) CREATE UNLOGGED TABLE was working with pg_class.relpersistence marked
as initially defined, but partitions did not inherit the UNLOGGED
property, which was confusing.

This commit causes the commands mentioned above to fail for partitioned
tables, instead.

pg_dump is tweaked so as partitioned tables marked as UNLOGGED ignore
the option when dumped from older server versions.  pgbench needs a
tweak for --unlogged and --partitions=N to ignore the UNLOGGED option on
the partitioned tables created, its partitions still being unlogged.

Author: Michael Paquier
Reviewed-by: Nathan Bossart
Discussion: https://postgr.es/m/ZiiyGFTBNkqcMQi_@paquier.xyz

Branch
------
master

Details
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https://git.postgresql.org/pg/commitdiff/e2bab2d792044b55dd092bf1c2be0d570ccb9401

Modified Files
--------------
doc/src/sgml/ref/alter_table.sgml          |  4 ++++
doc/src/sgml/ref/create_table.sgml         |  4 ++++
src/backend/commands/tablecmds.c           |  9 +++++++--
src/bin/pg_dump/pg_dump.c                  |  7 ++++++-
src/bin/pgbench/pgbench.c                  |  2 +-
src/test/regress/expected/create_table.out | 10 ++++++++++
src/test/regress/sql/create_table.sql      |  6 ++++++
7 files changed, 38 insertions(+), 4 deletions(-)