Implement the TMC2130 IOIN register version (#328)

The IOIN register contains some read-only state, along with the
driver version which can be used for IC checking.

Implement two fields (a fixed one and the version) for this purpose.

parts/components/TMC2130.cpp

@@ -303,6 +303,9 @@ void TMC2130::Init(struct avr_t * avr)
 	TH.AddTrace(this, DIR_IN,{TC::OutputPin, TC::Stepper});
 	TH.AddTrace(this, ENABLE_IN,{TC::OutputPin, TC::Stepper});
 	TH.AddTrace(this, DIAG_OUT,{TC::InputPin, TC::Stepper});
+
+	m_regs.defs.IOIN.one = 0x1;
+	m_regs.defs.IOIN.version = 0x11;
 }
 
 float TMC2130::StepToPos(int32_t step)

parts/components/TMC2130.h

@@ -160,7 +160,16 @@ class TMC2130: public SPIPeripheral, public Scriptable, public GLMotor
                     uint8_t uv_cp   :1;
 					uint32_t :29; // unused
                 }  __attribute__ ((__packed__)) GSTAT;
-                uint32_t _unimplemented[106]; //0x02 - 0x6B
+                uint32_t _unimplemented[2]; //0x02 - 0x03
+                struct                 // 0x04
+                {
+					uint8_t         :6;  // unused
+					uint8_t one     :1;  // always one
+					uint8_t         :1;  // unused
+					uint16_t        :16; // unused
+					uint8_t version :8;
+                }  __attribute__ ((__packed__)) IOIN;
+                uint32_t _unimplemented2[103]; //0x05 - 0x6B
 				struct                        //0x6C
 				{
 					uint32_t toff		:4;
@@ -181,7 +190,7 @@ class TMC2130: public SPIPeripheral, public Scriptable, public GLMotor
 					uint32_t diss2g		:1;
 					uint32_t			:1;
 				} __attribute__ ((__packed__)) CHOPCONF;
-                uint32_t _unimplemented2[2]; //0x6D - 0x6E
+                uint32_t _unimplemented3[2]; //0x6D - 0x6E
                 struct                       //0x6F
                 {
                     uint16_t SG_RESULT   :10;