favr-32-ezkit: Fix printf format warnings

Signed-off-by: Haavard Skinnemoen <haavard.skinnemoen@atmel.com>
diff --git a/include/configs/favr-32-ezkit.h b/include/configs/favr-32-ezkit.h
index 6f77c25..a27c02a 100644
--- a/include/configs/favr-32-ezkit.h
+++ b/include/configs/favr-32-ezkit.h
@@ -108,7 +108,7 @@
 #define CONFIG_AUTOBOOT			1
 #define CONFIG_AUTOBOOT_KEYED		1
 #define CONFIG_AUTOBOOT_PROMPT		\
-	"Press SPACE to abort autoboot in %d seconds\n"
+	"Press SPACE to abort autoboot in %d seconds\n", bootdelay
 #define CONFIG_AUTOBOOT_DELAY_STR	"d"
 #define CONFIG_AUTOBOOT_STOP_STR	" "