pgsql: doc: mention the pg_locks lock names in parentheses

doc: mention the pg_locks lock names in parentheses

Reported-by: Troy Frericks

Discussion: /messages/by-id/165653551130.665.8240515669521441325@wrigleys.postgresql.org

Backpatch-through: 10

Branch
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REL_11_STABLE

Details
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https://git.postgresql.org/pg/commitdiff/9d352c4448e98c96167bc8134958de7048697829

Modified Files
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doc/src/sgml/mvcc.sgml | 16 ++++++++--------
1 file changed, 8 insertions(+), 8 deletions(-)