message: Lift the restriction in the docs that while loops can't be nested.
diff: @@ -2385,8 +2385,6 @@ restrictions listed below.
  last execution of the `body`.
  * The shape of the type `T` is statically determined and must be the same
  across all iterations.
  -* `While` nodes are not allowed to be nested. (This restriction may be lifted
  - in the future on some targets.)
  The T parameters of the computations are initialized with the `init` value in
  the first iteration and are automatically updated to the new result from `body`
  