make doxygen include documentation for SuperLU

[[Imported from SVN: r838]]

doc/doxygen/Doxyfile

@@ -995,7 +995,7 @@ INCLUDE_FILE_PATTERNS  =
 # undefined via #undef or recursively expanded use the := operator 
 # instead of the = operator.
 
-PREDEFINED             = DOXYGEN HAVE_MPI:=1
+PREDEFINED             = DOXYGEN HAVE_MPI:=1 HAVE_SUPERLU
 
 # If the MACRO_EXPANSION and EXPAND_ONLY_PREDEF tags are set to YES then 
 # this tag can be used to specify a list of macro names that should be expanded.