Resolve "Check suspicious Q format in ProcessIGF_fx()"

Reason why this change is needed

• There may be a bug in:

  tns_predictionGain = L_deposit_l( hIGFEnc->tns_predictionGain ); // todo: mul, 2026-03-12: check, why this is in Q23
  IF( LT_32( tns_predictionGain, ONE_POINT_ONE_FIVE_Q23 ) && LT_16( predictionGain, ONE_POINT_ONE_FIVE_Q7 ) )
  {
      hIGFEnc->flatteningTrigger = 1;
      move16();
  }
  ELSE
  {
      hIGFEnc->flatteningTrigger = 0;
      move16();
  }

  It should be L_deposit_h to obtain Q23 out of Q7 - lets check

• EVS branch should be BE --> make fix dependend on element_mode

Closes #2548 (closed)