pgsql: doc: correct reference to pg_relation in comment

doc: correct reference to pg_relation in comment

Reported-by: Dagfinn Ilmari Mannsåker

Discussion: /messages/by-id/87sf9apnr0.fsf@wibble.ilmari.org

Backpatch-through: master

Branch
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master

Details
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https://git.postgresql.org/pg/commitdiff/441bbd298888fe751a01b6c74cc53f2e7b223fa9

Modified Files
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src/backend/storage/large_object/inv_api.c | 10 +++++-----
1 file changed, 5 insertions(+), 5 deletions(-)