Restoring changes that was accidentally excluded when merging the lastest state changes from the bcmi-labs master branch

Author: Bekken, Kristian_saxrud

variants/uno2018/pins_arduino.h

@@ -56,8 +56,8 @@ static const uint8_t SCL = PIN_WIRE_SCL;
 // USART1 on mega4809 (alternative pins)
 // Mapped to HWSERIAL0 in Serial library
 #define HWSERIAL0 (&USART1)
-//!!BUG in device header file. The RXC and DRE vectors are swapped!!
 #define HWSERIAL0_DRE_VECTOR (USART1_DRE_vect)
+#define HWSERIAL0_DRE_VECTOR_NUM (USART1_DRE_vect_num)
 #define HWSERIAL0_RXC_VECTOR (USART1_RXC_vect)
 #ifdef REV_A_ENGINEERING_SAMPLE
 #define PIN_WIRE_HWSERIAL0_RX (12)
@@ -71,8 +71,8 @@ static const uint8_t SCL = PIN_WIRE_SCL;
 // USART3 on mega4809 (alternative pins)
 // Mapped to HWSERIAL1 in Serial library
 #define HWSERIAL1 (&USART3)
-//!!BUG in device header file. The RXC and DRE vectors are swapped!!
 #define HWSERIAL1_DRE_VECTOR (USART3_DRE_vect)
+#define HWSERIAL1_DRE_VECTOR_NUM (USART3_DRE_vect_num)
 #define HWSERIAL1_RXC_VECTOR (USART3_RXC_vect)
 #define PIN_WIRE_HWSERIAL1_RX (26)
 #define PIN_WIRE_HWSERIAL1_TX (27)
@@ -81,8 +81,8 @@ static const uint8_t SCL = PIN_WIRE_SCL;
 // USART0 on mega4809 (alternative pins)
 // Mapped to HWSERIAL2 in Serial library
 #define HWSERIAL2 (&USART0)
-//!!BUG in device header file. The RXC and DRE vectors are swapped!!
 #define HWSERIAL2_DRE_VECTOR (USART0_DRE_vect)
+#define HWSERIAL2_DRE_VECTOR_NUM (USART0_DRE_vect_num)
 #define HWSERIAL2_RXC_VECTOR (USART0_RXC_vect)
 #define PIN_WIRE_HWSERIAL2_RX (23)
 #define PIN_WIRE_HWSERIAL2_TX (24)