Fix configry for SuperLU detection.

config/pac.m4

@@ -635,7 +635,7 @@ if test "x$pac_slu_header_ok" == "xyes" ; then
     LIBS="$SLU_LIBS -lm $save_LIBS";
     AC_TRY_LINK_FUNC(superlu_malloc, 
 		     [mld2p4_cv_have_superlu=yes;pac_slu_lib_ok=yes;],
-		     [mld2p4_cv_have_superlu=no;pac_slu_lib_ok=no; SLU_LIBS=""; SLU_INCLUDES=""])
+		     [mld2p4_cv_have_superlu=no;pac_slu_lib_ok=no; SLU_LIBS="";])
  fi
  if test "x$pac_slu_lib_ok" == "xno" ; then 
     dnl Maybe lib64?