avr32: fixup definitions to ATMEL_BASE_xxx

Signed-off-by: Andreas Bießmann <biessmann@corscience.de>
diff --git a/include/configs/atstk1004.h b/include/configs/atstk1004.h
index 12c9414..344ba8f 100644
--- a/include/configs/atstk1004.h
+++ b/include/configs/atstk1004.h
@@ -85,10 +85,8 @@
  */
 #define CONFIG_SYS_PLL0_OPT			0x04
 
-#undef CONFIG_USART0
-#define CONFIG_USART1			1
-#undef CONFIG_USART2
-#undef CONFIG_USART3
+#define CONFIG_USART_BASE		ATMEL_BASE_USART1
+#define CONFIG_USART_ID			1
 
 /* User serviceable stuff */
 #define CONFIG_DOS_PARTITION		1