pgsql: Fix silly initializations (cosmetic only).

Fix silly initializations (cosmetic only).

Initializing a pointer to "false" isn't per project style,
and reportedly some compilers warn about it (though I've
not seen any such warnings in the buildfarm).

Seems to have come in with commit ff11e7f4b, so back-patch
to v12 where that was added.

Didier Gautheron

Discussion: https://postgr.es/m/CAJRYxu+XQuM0qnSqt1Ujztu6fBPzMMAT3VEn6W32rgKG6A2Fsw@mail.gmail.com

Branch
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REL_12_STABLE

Details
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https://git.postgresql.org/pg/commitdiff/99cc47b1d85aabc4a80910c839073f83a4fb163b

Modified Files
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src/backend/commands/trigger.c | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)