pgsql: doc: clarify which table creation is used for inheritance part.

doc:  clarify which table creation is used for inheritance part.

Previously people might assume that the partition syntax version of
CREATE TABLE is to be used for the inheritance partition table example;
mention that the non-partitioned version should be used.

Reported-by: mib@nic.at

Discussion: https://postgr.es/m/158089540905.1098.15071165437284409576@wrigleys.postgresql.org

Backpatch-through: 10

Branch
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master

Details
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https://git.postgresql.org/pg/commitdiff/d97d55460bbda698a8d3ca100bee5485255b888f

Modified Files
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doc/src/sgml/ddl.sgml | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)