pgsql: Fix variable lifespan in ExecInitCoerceToDomain().

Fix variable lifespan in ExecInitCoerceToDomain().

This undoes a mistake in 1ec7679f1: domainval and domainnull were
meant to live across loop iterations, but they were incorrectly
moved inside the loop. The effect was only to emit useless extra
EEOP_MAKE_READONLY steps, so it's not a big deal; nonetheless,
back-patch to v13 where the mistake was introduced.

Ranier Vilela

Discussion: https://postgr.es/m/CAEudQAqXuhbkaAp-sGH6dR6Nsq7v28_0TPexHOm6FiDYqwQD-w@mail.gmail.com

Branch
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REL_13_STABLE

Details
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https://git.postgresql.org/pg/commitdiff/ada667b45496998674818e135e9cd6580f1bc019

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