pgsql: Fix function return type confusion

Fix function return type confusion

When parse_hba_line's return type was changed from bool to a pointer,
the MANDATORY_AUTH_ARG macro wasn't adjusted.

This back-patches commit c74d586d2 into out-of-support branches,
pursuant to newly-established project policy. The point is to
suppress scary-looking warnings so that people building these
branches needn't expend brain cells verifying that it's safe
to ignore the warnings.

Discussion: /messages/by-id/d0316012-ece7-7b7e-2d36-9c38cb77cb3b@enterprisedb.com

Branch
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REL9_2_STABLE

Details
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https://git.postgresql.org/pg/commitdiff/468773837bed4051c9791fd2d6d2c9558daeacb7

Modified Files
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src/backend/libpq/hba.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)