pgsql: doc: Add link to listen_addresses as cause of connection failure

doc: Add link to listen_addresses as cause of connection failure

Reported-by: k.man.113@gmail.com

Discussion: /messages/by-id/171494070007.703.17021965362263796980@wrigleys.postgresql.org

Backpatch-through: master

Branch
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master

Details
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https://git.postgresql.org/pg/commitdiff/1eb5564230a3b82f7f8e8b91b93114dbde66c811

Modified Files
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doc/src/sgml/runtime.sgml | 3 ++-
1 file changed, 2 insertions(+), 1 deletion(-)