pgsql: docs: add parameter with brackets around varbit()

docs: add parameter with brackets around varbit()

Reported-by: scott.ure@caseware.com

Discussion: /messages/by-id/152074343671.1853.18284519607571497106@wrigleys.postgresql.org

Author: Euler Taveira

Backpatch-through: 10

Branch
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master

Details
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https://git.postgresql.org/pg/commitdiff/681673e0c6c21a876e6ef7680e2116de60cf6286

Modified Files
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doc/src/sgml/datatype.sgml | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)