Revert "Merge branch 'M17_AX25_FM'"

This reverts commit e1427e3e37, reversing
changes made to bcdba292eb.

IIRDirectForm1Filter.cpp

@@ -1,60 +0,0 @@
-/*
- *   Copyright (C) 2015-2020 by Jonathan Naylor G4KLX
- *   Copyright (C) 2020 by Geoffrey Merck - F4FXL KC3FRA
- *
- *   This program is free software; you can redistribute it and/or modify
- *   it under the terms of the GNU General Public License as published by
- *   the Free Software Foundation; either version 2 of the License, or
- *   (at your option) any later version.
- *
- *   This program is distributed in the hope that it will be useful,
- *   but WITHOUT ANY WARRANTY; without even the implied warranty of
- *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
- *   GNU General Public License for more details.
- *
- *   You should have received a copy of the GNU General Public License
- *   along with this program; if not, write to the Free Software
- *   Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
- */
-
-#include "IIRDirectForm1Filter.h"
-#include "math.h"
-
-CIIRDirectForm1Filter::CIIRDirectForm1Filter(float b0, float b1, float b2, float , float a1, float a2, float addtionalGaindB) :
-m_x2(0.0F),
-m_y2(0.0F),
-m_x1(0.0F),
-m_y1(0.0F),
-m_b0(b0),
-m_b1(b1),
-m_b2(b2),
-m_a1(a1),
-m_a2(a2),
-m_additionalGainLin(0.0F)
-{
-  m_additionalGainLin = ::powf(10.0F, addtionalGaindB / 20.0F);
-}
-
-float CIIRDirectForm1Filter::filter(float sample)
-{
-  float output = m_b0 * sample
-               + m_b1 * m_x1 
-               + m_b2 * m_x2
-               - m_a1 * m_y1 
-               - m_a2 * m_y2;
-
-  m_x2 = m_x1;
-  m_y2 = m_y1;  
-  m_x1 = sample;
-  m_y1 = output;
-
-  return output * m_additionalGainLin;
-}
-
-void CIIRDirectForm1Filter::reset()
-{
-  m_x1 = 0.0f;
-  m_x2 = 0.0f;
-  m_y1 = 0.0f;
-  m_y2 = 0.0f;
-}