pgsql: Make some use of anonymous unions [plpython]

Make some use of anonymous unions [plpython]

Make some use of anonymous unions, which are allowed as of C11, as
examples and encouragement for future code, and to test compilers.

This commit changes some structures in plpython.

Reviewed-by: Chao Li <li(dot)evan(dot)chao(at)gmail(dot)com>
Discussion: https://www.postgresql.org/message-id/flat/f00a9968-388e-4f8c-b5ef-5102e962d997%40eisentraut.org

Branch
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master

Details
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https://git.postgresql.org/pg/commitdiff/8b7f27fef3e225e0b34f0d9f1a9f20770b72d01c

Modified Files
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src/pl/plpython/plpy_exec.c | 2 +-
src/pl/plpython/plpy_typeio.c | 134 +++++++++++++++++++++---------------------
src/pl/plpython/plpy_typeio.h | 4 +-
3 files changed, 70 insertions(+), 70 deletions(-)