include/linux/swap.h: remove unused leftovers

This removed unused leftovers, most of them are forward structure
declarations.  Also removes SWAP_BATCH macro which isn't used any where in
the code.

Found these during manual code review.

Link: https://lore.kernel.org/68591daf0d679e5a0072d63751f187d14613e2b0.1781146877.git.ritesh.list@gmail.com
Signed-off-by: Ritesh Harjani (IBM) <ritesh.list@gmail.com>
Reviewed-by: Barry Song <baohua@kernel.org>
Acked-by: Chris Li <chrisl@kernel.org>
Acked-by: David Hildenbrand (Arm) <david@kernel.org>
Cc: Baoquan He <baoquan.he@linux.dev>
Cc: Kairui Song <kasong@tencent.com>
Cc: Kemeng Shi <shikemeng@huaweicloud.com>
Cc: Nhat Pham <nphamcs@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
This commit is contained in:
Ritesh Harjani (IBM) 2026-06-11 08:39:32 +05:30 • committed by Andrew Morton
commit 567c26a132