pgsql: Code simplification

Code simplification

Initialize TriggerData to 0 for the whole struct together, instead of
each field separately.

Reviewed-by: Daniel Gustafsson <daniel@yesql.se>
Discussion: https://www.postgresql.org/message-id/flat/11c5f156-67a9-0fb5-8200-2a8018eb2e0c@2ndquadrant.com

Branch
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master

Details
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https://git.postgresql.org/pg/commitdiff/8f152b6c50c764d4c300e73a535da88cd1b18fa5

Modified Files
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src/backend/commands/tablecmds.c |  4 +--
src/backend/commands/trigger.c   | 78 ++++++----------------------------------
2 files changed, 12 insertions(+), 70 deletions(-)