pgsql: pg_dump: Reorganize dumpBaseType()

pg_dump: Reorganize dumpBaseType()

Along the same lines as ed2c7f65b and daa9fe8a5, reduce code duplication
by having just one copy of the parts of the query that are the same
across all server versions; and make the conditionals control the
smallest possible amount of code.  This is in preparation for adding
another dumpable field to pg_type.

Branch
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master

Details
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https://git.postgresql.org/pg/commitdiff/04732962462ba99cf8f8bcf6ac83932867cc96a8

Modified Files
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src/bin/pg_dump/pg_dump.c | 110 ++++++++++++++++------------------------------
1 file changed, 39 insertions(+), 71 deletions(-)