Fix Wire pin definitions on ItsyBitsy (#325)

Author: apendley

variants/adafruit_itsybitsy/pins_arduino.h

@@ -27,15 +27,13 @@
 #define PIN_SPI1_SS    (31u)
 
 // Wire
-#define PIN_WIRE0_SDA  (2u)
-#define PIN_WIRE0_SCL  (3u)
-
-// Not pinned out
-#define PIN_WIRE1_SDA  (31u)
-#define PIN_WIRE1_SCL  (31u)
+#define PIN_WIRE0_SDA  (24u)
+#define PIN_WIRE0_SCL  (25u)
+#define PIN_WIRE1_SDA  (2u)
+#define PIN_WIRE1_SCL  (3u)
 
 #define SERIAL_HOWMANY (2u)
 #define SPI_HOWMANY    (1u)
-#define WIRE_HOWMANY   (1u)
+#define WIRE_HOWMANY   (2u)
 
 #include "../generic/common.h"