[atkmm/atkmm-2-28] atkmm.h: Atkmm is used by gtkmm-3.0, not by gtkmm-4.0

[Kjell Ahlstedt <kjellahl src gnome org>]

commit 8b140429a8c5b2970bab57bb36303a1c72d31f2a
Author: Kjell Ahlstedt <kjellahlstedt gmail com>
Date:   Wed Dec 22 18:27:26 2021 +0100

    atkmm.h: Atkmm is used by gtkmm-3.0, not by gtkmm-4.0

 atk/atkmm.h | 6 ++++--
 1 file changed, 4 insertions(+), 2 deletions(-)
---
diff --git a/atk/atkmm.h b/atk/atkmm.h
index 4cd68df..2f36857 100644
--- a/atk/atkmm.h
+++ b/atk/atkmm.h
@@ -20,12 +20,14 @@
 #ifndef _ATKMM_H
 #define _ATKMM_H
 
-
 /** @mainpage atkmm Reference Manual
  *
  * @section description Description
  *
- * atkmm is the official C++ interface for the <a href="http://library.gnome.org/devel/atk/stable/";>ATK</a> 
accessibility toolkit library. It may be used, for instance, by user interfaces implemented with gtkmm.
+ * atkmm is the official C++ interface for the
+ * <a href="http://library.gnome.org/devel/atk/stable/";>ATK</a>
+ * accessibility toolkit library. It may be used, for instance, by user interfaces
+ * implemented with gtkmm-3.0.
  *
  * @section basics Basic usage
  *