Fixing typo in radixwidgets/CMakeLists

radixwidgets/CMakeLists.txt

@@ -58,10 +58,10 @@ ELSE()
        navigationwidget.cc
    )
    IF(TPL_ENABLE_VTK)
-      SET(HEADERS ${HEADER}
+      SET(HEADERS ${HEADERS}
           vtkchartwidget.hh
       )
-	  SET(SOURCES
+          SET(SOURCES
           ${SOURCES}
           vtkchartwidget.cc
       )