[Relay][heterogeneous] Fix tuple annotation

[zhiics]

This PR fixes the annotation on tuple nodes. The device type of TupleGetItem should be the same to the associated Tuple.

For example,

fn (%x: Tensor[(3, 3, 4), float32]) {
  %0 = split(%x, indices_or_sections=int64(3))
  %1 = on_device(%0, meta[relay.attrs.OnDeviceAttrs][0])
  %2 = %1.0
  %3 = %1.1
  subtract(%2, %3)
}

should return after rewrite_annotated_ops

fn (%x: Tensor[(3, 3, 4), float32]) {
  %0 = split(%x, indices_or_sections=int64(3))
  %1 = %0.0
  %2 = device_copy(%1, meta[relay.attrs.DeviceCopyAttrs][0])
  %3 = %0.1
  %4 = device_copy(%3, meta[relay.attrs.DeviceCopyAttrs][1])
  subtract(%2, %4)
}

cc @jroesch @yzhliu @imorinaga @jwfromm

[yzhliu]

Thanks!