ixp: move serial to drivers/serial

Signed-off-by: Jean-Christophe PLAGNIOL-VILLARD <plagnioj@jcrosoft.com>
diff --git a/include/configs/actux1.h b/include/configs/actux1.h
index 58d56ee..adbc399 100644
--- a/include/configs/actux1.h
+++ b/include/configs/actux1.h
@@ -39,6 +39,7 @@
 #define CONFIG_DISPLAY_CPUINFO		1
 #define CONFIG_DISPLAY_BOARDINFO	1
 
+#define CONFIG_IXP_SERIAL
 #define CONFIG_SYS_IXP425_CONSOLE		IXP425_UART2
 #define CONFIG_BAUDRATE			115200
 #define CONFIG_BOOTDELAY		3