Add changelog for #6493 smartplaylist quiet option

Author: JOJ0

docs/changelog.rst

@@ -86,6 +86,11 @@ New features
 - :doc:`plugins/lastgenre`: Add support for a user-configurable ignorelist to
   exclude unwanted or incorrect Last.fm (or existing) genres, either per artist
   or globally :bug:`6449`
+- :doc:`plugins/smartplaylist`: A ``--quiet`` flag is added to the ``splupdate``
+  command to suppress several log messages for each updated playlist and in
+  pretend mode only prints the playlist name and the number of tracks instead of
+  each track name. This can be useful when testing out new entries in the
+  configuration.
 
 Bug fixes
 ~~~~~~~~~