Module17: made M17 baseband output have correct DC bias and amplitude

Removed an old workaround for an hardware bug of Module17 rev 0.1b limiting
the output swing of baseband signal in newer hardware revisions.

Contribution by Mathis Schmieder DB9MAT.

openrtx/include/protocols/M17/M17Modulator.hpp

@@ -106,13 +106,8 @@ private:
     static constexpr size_t M17_SAMPLES_PER_SYMBOL = M17_TX_SAMPLE_RATE / M17_SYMBOL_RATE;
     static constexpr size_t M17_FRAME_SAMPLES      = M17_FRAME_SYMBOLS * M17_SAMPLES_PER_SYMBOL;
 
-    #ifdef PLATFORM_MOD17
-    static constexpr float  M17_RRC_GAIN          = 15000.0f;
-    static constexpr float  M17_RRC_OFFSET        = 11500.0f;
-    #else
     static constexpr float  M17_RRC_GAIN          = 23000.0f;
     static constexpr float  M17_RRC_OFFSET        = 0.0f;
-    #endif
 
     std::array< int8_t, M17_FRAME_SYMBOLS > symbols;
     std::unique_ptr< int16_t[] > baseband_buffer;  ///< Buffer for baseband audio handling.

platform/drivers/audio/audio_Mod17.c

@@ -43,7 +43,7 @@ static const uint8_t pathCompatibilityMatrix[9][9] =
 const struct audioDevice outputDevices[] =
 {
     {NULL,                    0,                   0,             SINK_MCU},
-    {&stm32_dac_audio_driver, (const void *) 1365, STM32_DAC_CH1, SINK_RTX},
+    {&stm32_dac_audio_driver, (const void *) 2048, STM32_DAC_CH1, SINK_RTX},
     {&stm32_dac_audio_driver, 0,                   STM32_DAC_CH2, SINK_SPK},
 };