mx6sx: udoo_neo: Define the default serial console

Standard boot processes including distro boot generally expect the
default console to be defined.

Signed-off-by: Peter Robinson <pbrobinson@gmail.com>
Tested-by: Breno Lima <breno.lima@nxp.com>
diff --git a/include/configs/udoo_neo.h b/include/configs/udoo_neo.h
index 23a3685..5b46272e 100644
--- a/include/configs/udoo_neo.h
+++ b/include/configs/udoo_neo.h
@@ -30,6 +30,7 @@
 /* Linux only */
 #define CONFIG_ENV_VARS_UBOOT_RUNTIME_CONFIG
 #define CONFIG_EXTRA_ENV_SETTINGS \
+	"console=ttymxc0,115200\0" \
 	"fdt_high=0xffffffff\0" \
 	"initrd_high=0xffffffff\0" \
 	"fdtfile=undefined\0" \