pgsql: Reduce scope of for-loop-local variables to avoid shadowing

Reduce scope of for-loop-local variables to avoid shadowing

Adjust a couple of for-loops where a local variable was shadowed by
another in the same scope, by renaming it as well as reducing its scope
to the containing for-loop.

Author: Chao Li <lic(at)highgo(dot)com>
Reviewed-by: Peter Smith <smithpb2250(at)gmail(dot)com>
Reviewed-by: Álvaro Herrera <alvherre(at)kurilemu(dot)de>
Discussion: https://postgr.es/m/CAEoWx2kQ2x5gMaj8tHLJ3=jfC+p5YXHkJyHrDTiQw2nn2FJTmQ@mail.gmail.com

Branch
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master

Details
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https://git.postgresql.org/pg/commitdiff/cece37c9843c980b5be2f6d24c2b9cef1f9429a7

Modified Files
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src/backend/backup/basebackup_incremental.c | 10 ++++------
src/backend/parser/parse_target.c | 10 ++++------
2 files changed, 8 insertions(+), 12 deletions(-)