[gi-docgen] docs: Be more explicit on the role of the `type` fragment

[Emmanuele Bassi <ebassi src gnome org>]

commit 1a713a4b727e8a827095dfd25fe998c59bdde125
Author: Emmanuele Bassi <ebassi gnome org>
Date:   Tue May 25 18:09:38 2021 +0100

    docs: Be more explicit on the role of the `type` fragment
    
    The `type` fragment can be used with any type.

 docs/linking.rst | 3 +++
 1 file changed, 3 insertions(+)
---
diff --git a/docs/linking.rst b/docs/linking.rst
index 70cf8df..fc2858d 100644
--- a/docs/linking.rst
+++ b/docs/linking.rst
@@ -111,6 +111,9 @@ relative to the current namespace:
     // Equivalent to [enum@Gtk.Orientation]
     [type@Gtk.Orientation]
 
+Anything that is a known type—aliases, callbacks, classes, constants,
+enumerations, interfaces, structures—can be linked using the ``type`` fragment.
+
 Additionally, the ``id`` fragment, followed by a C symbol identifier, will try
 to link to the function; for instance: