SVD generator: redundant cluster layer

[hegza]

SVD files generated from IP-XACT memory maps typically have a redundant cluster layer even when not always necessary. I'm guessing the UI might be enforcing this.

<peripheral>periph</peripheral>
  <cluster>cluster</cluster> <!-- This layer shouldn't be necessary. -->
    <register>reg0</register>
    <register>reg1</register>
    ...

<peripheral>periph</peripheral>
  <!-- Registers can be defined at this layer already. -->
  <register>reg0</register>
  <register>reg1</register>
  ...

We see in the output that there's usually some workaround looking thing like <cluster>registers</cluster>.