pgsql: Allow VACUUM FULL/CLUSTER to bump freeze horizons even for pg_cl

Allow VACUUM FULL/CLUSTER to bump freeze horizons even for pg_class.

pg_class is a special case for CLUSTER and VACUUM FULL, so although
commit 3cff1879f8d03cb729368722ca823a4bf74c0cac caused these
operations to advance relfrozenxid and relminmxid for all other
tables, it did not provide the same benefit for pg_class.  This
plugs that gap.

Andres Freund

Branch
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master

Details
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http://git.postgresql.org/pg/commitdiff/af2543e884db06c0beb75010218cd88680203b86

Modified Files
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src/backend/commands/cluster.c |   37 ++++++++++++++++++++++++++++++++++++-
1 file changed, 36 insertions(+), 1 deletion(-)