UPSTREAM: zram: filter out recomp targets based on priority

Do no select for post processing slots that are already compressed with
same or higher priority compression algorithm.

This should save some memory, as previously we would still put those
entries into corresponding post-processing buckets and filter them out
later in recompress_slot().

Link: https://lkml.kernel.org/r/20250303022425.285971-10-senozhatsky@chromium.org


Signed-off-by: Sergey Senozhatsky <senozhatsky@chromium.org>
Cc: Hillf Danton <hdanton@sina.com>
Cc: Kairui Song <ryncsn@gmail.com>
Cc: Minchan Kim <minchan@kernel.org>
Cc: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Cc: Yosry Ahmed <yosry.ahmed@linux.dev>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
(cherry picked from commit 9724bef9)

Bug: 446676432
Change-Id: Ie5222ba24ea55b8a36dc966f4b40ed7bc76717b7
Signed-off-by: David Stevens <stevensd@google.com>