ACD_Mask

Need to change outermost node to acdMask.

  <acdMask>
    <!-- only expect masked off channels -->
    <GARC ID="0">
      <GAFE ID="0">
        <!-- Mask off unwanted functionality -->
        <mask_veto_afe/>Veto discriminator in FE
        <mask_hld_afe/>HLD discriminator in FE
        <mask_veto_arc/>VETO signal in GARC 
        <mask_pha_arc/>PHA signal in GARC
      </GAFE>
    </GARC>
  </acdMask>