add I2C dummy

Author: sabas1080

variants/catsniffer/variant.h

@@ -154,7 +154,12 @@ static const uint8_t SCK  = PIN_SPI_SCK ;
 /*
  * Wire Interfaces
  */
-#define WIRE_INTERFACES_COUNT 0
+#define WIRE_INTERFACES_COUNT 1
+
+#define PIN_WIRE_SDA         -1
+#define PIN_WIRE_SCL         -1
+#define PERIPH_WIRE          sercom2
+//#define WIRE_IT_HANDLER    // hack! we call the i2c handler from within the serial handler!
 
 /*
  * USB