main libiio api doc: Add "back" url at the top of the mainpage

rgetz · rgetz · commit 5fb5d4aebcad · 2020-04-17T23:14:50.000-04:00
Signed-off-by: Robin Getz &lt;robin.getz@analog.com&gt;
diff --git a/mainpage.dox b/mainpage.dox
@@ -3,6 +3,8 @@
 
 @tableofcontents
 
+<a href="../index.html">Back to libIIO</a>
+
 @section license License
 Libiio has been developed and is released under the terms of the GNU Lesser General Public
 License, version 2 or (at your option) any later version.
