doc(dispatch): add doc on Indexed and Composite array dispatch

Documentation/dev/build.md

@@ -394,6 +394,12 @@ currently exist for use with the VTK dispatch mechanism:
     `vtkConstantArray` as part of the implicit array framework
   * `VTK_DISPATCH_STD_FUNCTION_ARRAYS` (default `OFF`): includes dispatching for arrays with
     an `std::function` backend `vtkStdFunctionArray` as part of the implicit array framework
+  * `VTK_DISPATCH_COMPOSITE_ARRAYS` (default `OFF`): includes dispatching of arrays with a
+    `vtkCompositeImplicitBackend` backend, `vtkCompositeArray`, as part of the implicit array
+    framework
+  * `VTK_DISPATCH_INDEXED_ARRAYS` (default `OFF`): includes dispatching of arrays with a
+    `vtkIndexedImplicitBackend` backend, `vtkIndexedArray`, as part of the implicit array
+    framework
 
 The outlier in terms of dispatch support is the family of arrays derived from
 `vtkScaledSOADataArrayTemplate` which are automatically included in dispatch when built setting