doc: add pendingreleasenotes for cephfs subvolume earmarking feature

Signed-off-by: Avan Thakkar <[email protected]>

Author: avanthakkar

PendingReleaseNotes

@@ -13,6 +13,15 @@
   output is changed from 'STATUS' to 'STATE'. The state of a group snapshot
   that was shown as 'ok' is now shown as 'complete', which is more descriptive.
 
+>=19.2.1
+
+* CephFS: Command `fs subvolume create` now allows tagging subvolumes through option
+  `--earmark` with a unique identifier needed for NFS or SMB services. The earmark
+  string for a subvolume is empty by default. To remove an already present earmark,
+  an empty string can be assigned to it. Additionally, commands
+  `ceph fs subvolume earmark set`, `ceph fs subvolume earmark get` and
+  `ceph fs subvolume earmark rm` have been added to set, get and remove earmark from a given subvolume.
+
 >=19.0.0
 
 * cephx: key rotation is now possible using `ceph auth rotate`. Previously,