[devhelp] Settings: better document the ::books-disabled-changed signal

[Sébastien Wilmet <swilmet src gnome org>]

commit 74ace3312a23c729e3180bb4d41661fc6a15641c
Author: Sébastien Wilmet <swilmet gnome org>
Date:   Sun Apr 29 09:42:53 2018 +0200

    Settings: better document the ::books-disabled-changed signal

 devhelp/dh-settings.c |    1 +
 1 files changed, 1 insertions(+), 0 deletions(-)
---
diff --git a/devhelp/dh-settings.c b/devhelp/dh-settings.c
index f816804..fab7344 100644
--- a/devhelp/dh-settings.c
+++ b/devhelp/dh-settings.c
@@ -303,6 +303,7 @@ dh_settings_class_init (DhSettingsClass *klass)
 
         /**
          * DhSettings::books-disabled-changed:
+         * @settings: the #DhSettings emitting the signal.
          *
          * The ::books-disabled-changed signal is emitted when the
          * "books-disabled" #GSettings key changes.