The index should only be included if the build of the sub-folder is done
with the html-builder (HTML output).
Signed-off-by: Markus Heiser <markus.heiser@darmarit.de>
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
    mac80211
    mac80211-advanced
 
-.. only::  subproject
+.. only::  subproject and html
 
    Indices
    =======
 
    java
    bad-memory
    basic-profiling
+
+.. only::  subproject and html
+
+   Indices
+   =======
+
+   * :ref:`genindex`
+
 
    vga-switcheroo
    vgaarbiter
 
-.. only::  subproject
+.. only::  subproject and html
 
    Indices
    =======
 
    volatile-considered-harmful
 
    development-process
+
+
+.. only::  subproject and html
+
+   Indices
+   =======
+
+   * :ref:`genindex`