docs: ext4.rst: add encryption and verity to features list

Mention encryption and verity in the ext4 features list.
Signed-off-by: Eric Biggers <ebiggers@google.com>
Link: https://lore.kernel.org/r/20191226154007.4569-1-ebiggers@kernel.orgSigned-off-by: Theodore Ts'o <tytso@mit.edu>

Documentation/admin-guide/ext4.rst

@@ -92,6 +92,8 @@ Currently Available
 * efficient new ordered mode in JBD2 and ext4 (avoid using buffer head to force
   the ordering)
 * Case-insensitive file name lookups
+* file-based encryption support (fscrypt)
+* file-based verity support (fsverity)
 
 [1] Filesystems with a block size of 1k may see a limit imposed by the
 directory hash tree having a maximum depth of two.