pgsql: pg_archivecleanup: Refactor loop doing old segment removals

pg_archivecleanup: Refactor loop doing old segment removals

This commit refactors a bit the main loop of pg_archivecleanup that
handles the removal of old segments, reducing by one its level of
indentation. This will help an incoming patch that adds a new option
related to the segment filtering logic.

Author: Atsushi Torikoshi
Reviewed-by: Kyotaro Horiguchi, Fujii Masao, Michael Paquier
Discussion: /messages/by-id/d660ef741ce3d82f3b4283f1cafd576c@oss.nttdata.com

Branch
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master

Details
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https://git.postgresql.org/pg/commitdiff/4a7556f77c44d295241d2432094b40156f69be1a

Modified Files
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src/bin/pg_archivecleanup/pg_archivecleanup.c | 128 +++++++++++++-------------
1 file changed, 66 insertions(+), 62 deletions(-)