Include lib8tion.c into RGB/LED matrix build list (#12699)

Co-authored-by: filterpaper <filterpaper@localhost>

common_features.mk

@@ -237,6 +237,7 @@ endif
     SRC += $(QUANTUM_DIR)/process_keycode/process_backlight.c
     SRC += $(QUANTUM_DIR)/led_matrix/led_matrix.c
     SRC += $(QUANTUM_DIR)/led_matrix/led_matrix_drivers.c
+    SRC += $(LIB_PATH)/lib8tion/lib8tion.c
     CIE1931_CURVE := yes
 
     ifeq ($(strip $(LED_MATRIX_DRIVER)), IS31FL3731)
@@ -265,6 +266,7 @@ endif
     SRC += $(QUANTUM_DIR)/color.c
     SRC += $(QUANTUM_DIR)/rgb_matrix/rgb_matrix.c
     SRC += $(QUANTUM_DIR)/rgb_matrix/rgb_matrix_drivers.c
+    SRC += $(LIB_PATH)/lib8tion/lib8tion.c
     CIE1931_CURVE := yes
     RGB_KEYCODES_ENABLE := yes