Merge pull request #51651 from zdover23/wip-doc-2023-05-22-cache-tiering-deprecation...

doc: note deprecation of Cache Tiering in Reef

Reviewed-by: Anthony D'Atri <anthony.datri@gmail.com>

diff --cc doc/rados/operations/cache-tiering.rst
index cd29b87d0cfa67c2c20f6d65bea31c2e6b9e1934,5d9e4c46562ec98b68eaa94fcb6c54646cb45c79..b2b235d628edd8c7a2a99a2acc1f0a2fbf442d93
--- 1/doc/rados/operations/cache-tiering.rst
--- 2/doc/rados/operations/cache-tiering.rst
+++ b/doc/rados/operations/cache-tiering.rst
@@@ -1,11 -1,9 +1,13 @@@
  ===============
   Cache Tiering
  ===============
 +.. warning:: Cache tiering has been deprecated in the Reef release as it
 +             has lacked a maintainer for a very long time. This does not mean
 +             it will be certainly removed, but we may choose to remove it
 +             without much further notice.
  
+ .. note:: Cache tiering is deprecated in Reef.
+ 
  A cache tier provides Ceph Clients with better I/O performance for a subset of
  the data stored in a backing storage tier. Cache tiering involves creating a
  pool of relatively fast/expensive storage devices (e.g., solid state drives)