message: Fix TF control dialect loop example to use .source/.sink instead of .value/.user for NextIteration (aligns with the converter implementation).
diff: @@ -41,7 +41,7 @@ func @LoopTest() {
  %0:2 = "_tf.Const"() {device = "", name = "Const", dtype = "tfdtype$DT_INT32", value = dense<1> : tensor<i32>} : () -> (tensor<i32>, !_tf.control)
  %1:2 = "_tf.Enter"(%0#0) {device = "", name = "while/Enter", T = "tfdtype$DT_INT32", frame_name = "while/while_context", is_constant = false, parallel_iterations = 10} : (tensor<i32>) -> (tensor<*xi32>, !_tf.control)
  - %11:3 = "_tf.NextIteration.value"() {device = "", name = "while/NextIteration", T = "tfdtype$DT_INT32", id = 0} : () -> (tensor<*xi32>, tensor<*xi32>, !_tf.control)
  + %11:2 = "_tf.NextIteration.source"() {device = "", name = "while/NextIteration", T = "tfdtype$DT_INT32", id = 0} : () -> (tensor<*xi32>, !_tf.control)
  %2:3 = "_tf.Merge"(%11#0, %1#0) {device = "", name = "while/Merge", N = 2, T = "tfdtype$DT_INT32"} : (tensor<*xi32>, tensor<*xi32>) -> (tensor<*xi32>, tensor<i32>, !_tf.control)
  %3:2 = "_tf.Const"(%2#2) {device = "", name = "while/Less/y", dtype = "tfdtype$DT_INT32", value = dense<2> : tensor<i32>} : (!_tf.control) -> (tensor<i32>, !_tf.control)
  @@ -52,6 +52,6 @@ func @LoopTest() {
  %8:2 = "_tf.Identity"(%6#1) {device = "", name = "while/Identity", T = "tfdtype$DT_INT32"} : (tensor<*xi32>) -> (tensor<*xi32>, !_tf.control)
  %9:2 = "_tf.Const"(%8#1) {device = "", name = "while/Add/y", dtype = "tfdtype$DT_INT32", value = dense<3> : tensor<i32>} : (!_tf.control) -> (tensor<i32>, !_tf.control)
  %10:2 = "_tf.Add"(%8#0, %9#0) {device = "", name = "while/Add", T = "tfdtype$DT_INT32"} : (tensor<*xi32>, tensor<i32>) -> (tensor<*xi32>, !_tf.control)
  - "_tf.NextIteration.user"(%10#0) {device = "", name = "while/NextIteration", T = "tfdtype$DT_INT32", id = 0} : (tensor<*xi32>) -> ()
  + %ctl = "_tf.NextIteration.sink"(%10#0) {device = "", name = "while/NextIteration", T = "tfdtype$DT_INT32", id = 0} : (tensor<*xi32>) -> (!_tf.control)
  return
  }
  