document --enable-maxnodes

doc/doxygen/chapters/41configure_options.doxy

@@ -298,6 +298,15 @@ Specify the maximum number of MIC threads
 Disable asynchronous copies between CPU and MIC devices.
 </dd>
 
+<dt>--enable-maxnodes=<c>count</c></dt>
+<dd>
+\anchor enable-maxnodes
+\addindex __configure__--enable-maxnodes
+Use at most <c>count</c> memory nodes.  This information is then available as
+the macro ::STARPU_MAXNODES. Reducing it allows to considerably reduce memory
+used by StarPU data structures.
+</dd>
+
 </dl>
 
 \section ExtensionConfiguration Extension Configuration