pgsql: Formatting cleanup of guc_tables.c

Formatting cleanup of guc_tables.c

This cleans up a few minor formatting inconsistencies.

Reviewed-by: John Naylor <johncnaylorls@gmail.com>
Discussion: https://www.postgresql.org/message-id/flat/dae6fe89-1e0c-4c3f-8d92-19d23374fb10%40eisentraut.org

Branch
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master

Details
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https://git.postgresql.org/pg/commitdiff/878656dbde0d2fd4b85a8c63566e2a9f0d0f4952

Modified Files
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src/backend/utils/misc/guc_tables.c | 238 +++++++++++++++++++++++-------------
1 file changed, 155 insertions(+), 83 deletions(-)