fixed USART2 pin naming (not USART3)

Author: ppescher

sam/1.0.4/variants/geolink_opentracker/variant.cpp

@@ -352,10 +352,10 @@ void init( void )
     g_APinDescription[PINS_USART1].ulPin,
     g_APinDescription[PINS_USART1].ulPinConfiguration);
   PIO_Configure(
-    g_APinDescription[PINS_USART3].pPort,
-    g_APinDescription[PINS_USART3].ulPinType,
-    g_APinDescription[PINS_USART3].ulPin,
-    g_APinDescription[PINS_USART3].ulPinConfiguration);
+    g_APinDescription[PINS_USART2].pPort,
+    g_APinDescription[PINS_USART2].ulPinType,
+    g_APinDescription[PINS_USART2].ulPin,
+    g_APinDescription[PINS_USART2].ulPinConfiguration);
 
   // Initialize USB pins
   PIO_Configure(

sam/1.0.4/variants/geolink_opentracker/variant.h

@@ -137,7 +137,7 @@ static const uint8_t SCK  = PIN_SPI_SCK;
 // Serial2
 #define PINS_USART1          (43u)
 // Serial3
-#define PINS_USART3          (44u)
+#define PINS_USART2          (44u)
 
 /*
  * USB Interfaces