pgsql: Make some use of anonymous unions [reorderbuffer xact_time]

Make some use of anonymous unions [reorderbuffer xact_time]

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 the ReorderBufferTXN struct.

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/57d46dff9b0ba8dc50fb37166373ea7638ecd2b9

Modified Files
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contrib/test_decoding/test_decoding.c | 12 ++++++------
src/backend/replication/logical/proto.c | 14 +++++++-------
src/backend/replication/logical/reorderbuffer.c | 14 +++++++-------
src/backend/replication/pgoutput/pgoutput.c | 2 +-
src/include/replication/reorderbuffer.h | 2 +-
5 files changed, 22 insertions(+), 22 deletions(-)