arm/fsl-ls: Add CONFIG_OF_STDOUT_VIA_ALIAS

This will allow OF-based earlycon to be used once the appropriate
aliases are added to the device tree and kernel support is fixed.

Signed-off-by: Scott Wood <scottwood@freescale.com>
Reviewed-by: York Sun <yorksun@freescale.com>
diff --git a/include/configs/ls1021aqds.h b/include/configs/ls1021aqds.h
index b8477e8..afef02f 100644
--- a/include/configs/ls1021aqds.h
+++ b/include/configs/ls1021aqds.h
@@ -658,6 +658,7 @@
 
 #define CONFIG_OF_LIBFDT
 #define CONFIG_OF_BOARD_SETUP
+#define CONFIG_OF_STDOUT_VIA_ALIAS
 #define CONFIG_CMD_BOOTZ
 
 #define CONFIG_MISC_INIT_R