pgsql: Update comment related to C99

Update comment related to C99

One could do more work here to eliminate the Windows difference
described in the comment, but that can be a separate project. The
purpose of this change is to update comments that might confusingly
indicate that C99 is not required.

Reviewed-by: Thomas Munro <thomas.munro@gmail.com>
Discussion: /messages/by-id/170308e6-a7a3-4484-87b2-f960bb564afa@eisentraut.org

Branch
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master

Details
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https://git.postgresql.org/pg/commitdiff/376c649634bb3fbfad79940f996e2fcb4c2ea6bf

Modified Files
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src/bin/pg_dump/dumputils.h | 7 ++++---
1 file changed, 4 insertions(+), 3 deletions(-)