pgsql: Some stylistic improvements in toast_save_datum()

Some stylistic improvements in toast_save_datum()

Move some variables to a smaller scope. Initialize chunk_data before
storing a pointer to it; this avoids compiler warnings on clang-21, or
respectively us having to work around it by initializing it to zero
before the variable is used (as was done in commit e92677e8633).

Discussion: https://www.postgresql.org/message-id/flat/6604ad6e-5934-43ac-8590-15113d6ae4b1%40eisentraut.org

Branch
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master

Details
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https://git.postgresql.org/pg/commitdiff/748caa9dcb686a84f239ee2cc08030d7c1efddd4

Modified Files
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src/backend/access/common/toast_internals.c | 39 ++++++++++++-----------------
1 file changed, 16 insertions(+), 23 deletions(-)