when doing AGC reset, call Calibrate(0x7F)

1. warm sleep
2. wake to stdby
3. Calibrate(0x7F) to reset all internal blocks
4. re-apply DIO2 RF / boosted gain & register patch to make sure
everything is as it was

src/helpers/radiolib/RadioLibWrappers.h

@@ -16,6 +16,7 @@ protected:
   void startRecv();
   float packetScoreInt(float snr, int sf, int packet_len);
   virtual bool isReceivingPacket() =0;
+  virtual void doResetAGC();
 
 public:
   RadioLibWrapper(PhysicalLayer& radio, mesh::MainBoard& board) : _radio(&radio), _board(&board) { n_recv = n_sent = 0; }