kho: test: clean up residual memory upon test_kho module unload

kho: test: clean up residual memory upon test_kho module unload

During the initialization phase, the test_kho module invokes the
kho_preserve_folio function, which internally configures bitmaps within
kho_mem_track and establishes chunk linked lists in KHO.  Upon unloading
the test_kho module, it is necessary to clean up these states.

Link: https://lkml.kernel.org/r/20260107022427.4114424-1-longwei27@huawei.com
Signed-off-by: Long Wei <longwei27@huawei.com>
Acked-by: Mike Rapoport (Microsoft) <rppt@kernel.org>
Cc: Alexander Graf <graf@amazon.com>
Cc: hewenliang <hewenliang4@huawei.com>
Cc: Pasha Tatashin <pasha.tatashin@soleen.com>
Cc: Pratyush Yadav <pratyush@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>