mm/zswap: s/red-black tree/xarray/

Changes made by commit 796c2c23e14e ("zswap: replace RB tree with xarray")
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Link: https://lkml.kernel.org/r/[e-mail]
Signed-off-by: SeongJae Park <[e-mail]>
Acked-by: Yosry Ahmed <[e-mail]>
Acked-by: Nhat Pham <[e-mail]>
Reviewed-by: Chengming Zhou <[e-mail]>
Cc: Chris Li <[e-mail]>
Cc: David Hildenbrand <[e-mail]>
Cc: Johannes Weiner <[e-mail]>
Cc: Jonathan Corbet <[e-mail]>
Cc: Liam Howlett <[e-mail]>
Cc: Lorenzo Stoakes <[e-mail]>
Cc: Michal Hocko <[e-mail]>
Cc: Mike Rapoport <[e-mail]>
Cc: Muchun Song <[e-mail]>
Cc: Roman Gushchin <[e-mail]>
Cc: Shakeel Butt <[e-mail]>
Cc: Suren Baghdasaryan <[e-mail]>
Cc: Vlastimil Babka <[e-mail]>
Signed-off-by: Andrew Morton <[e-mail]>

mm/zswap.c

···
  * This structure contains the metadata for tracking a single compressed
  * page within zswap.
  *
- * swpentry - associated swap entry, the offset indexes into the red-black tree
+ * swpentry - associated swap entry, the offset indexes into the xarray
  * length - the length in bytes of the compressed page data.  Needed during
  *          decompression.
  * referenced - true if the entry recently entered the zswap pool. Unset by the