message: Add missing reference to struct in python docs
diff: @@ -154,6 +154,9 @@ Shader Messages
  .. autoclass:: renderdoc.ShaderPixelMessageLocation
  :members:
  +.. autoclass:: renderdoc.ShaderGeometryMessageLocation
  + :members:
  +
  .. autoclass:: renderdoc.ShaderComputeMessageLocation
  :members:
  