Update desktop file in support of commit 90793c2c.

tderadio3/src/tderadio.desktop

@@ -3,13 +3,7 @@ Encoding=UTF-8
 Type=Application
 Exec=tderadio -caption "%c" %i %m
 Icon=tderadio
-# Restore the following key and remove this comment when a help handbook
-# is written. Disabling this key prevents populating the main handbook
-# table of contents with a non-existent document, which results in a
-# main handbook error message of
-# 'There is no documentation available for /xyz/index.html.'
-# Also disable this key when there exists only a useless template handbook.
-# DocPath=tderadio/index.html
+DocPath=tderadio/index.html
 Comment=Audio player for Internet and AM/FM Radio
 Comment[de]=
 Terminal=false