Fix ErgoTravel Board

It was not properly including the "config_common" files, and was causing it to break on the configurator.

Additionally, updated this to use the split common code.

keyboards/ergotravel/keymaps/viet/config.h

@@ -15,10 +15,7 @@ You should have received a copy of the GNU General Public License
 along with this program.  If not, see <http://www.gnu.org/licenses/>.
 */
 
-#ifndef CONFIG_USER_H
-#define CONFIG_USER_H
-
-#include "config_common.h"
+#pragma once
 
 /* Use I2C or Serial, not both */
 
@@ -39,4 +36,3 @@ along with this program.  If not, see <http://www.gnu.org/licenses/>.
 #define RGBLIGHT_VAL_STEP 20
 #define RGBLIGHT_LIMIT_VAL 220
 
-#endif

keyboards/ergotravel/keymaps/viet/rules.mk

@@ -2,6 +2,3 @@ RGBLIGHT_ENABLE = yes
 BACKLIGHT_ENABLE = no
 UNICODE_ENABLE = yes
 
-ifndef QUANTUM_DIR
-	include ../../../../Makefile
-endif