implement Wire.end() for SAMD core

Author: sandeepmistry

libraries/Wire/Wire.cpp

@@ -49,6 +49,10 @@ void TwoWire::begin(uint8_t address) {
   sercom->enableWIRE();
 }
 
+void TwoWire::end() {
+  sercom->disableWIRE();
+}
+
 void TwoWire::setClock(uint32_t frequency) {
 	// dummy funtion
 }

libraries/Wire/Wire.h

@@ -28,12 +28,16 @@
 
 #define BUFFER_LENGTH 32
 
+ // WIRE_HAS_END means Wire has end()
+#define WIRE_HAS_END 1
+
 class TwoWire : public Stream
 {
   public:
     TwoWire(SERCOM *s, uint8_t pinSDA, uint8_t pinSCL);
     void begin();
     void begin(uint8_t);
+    void end();
     void setClock(uint32_t); // dummy function
 
     void beginTransmission(uint8_t);