Specifically, only add the split_common folder to COMMON_VPATH if the feature is eanbled, to prevent issues with compilation
COMMON_VPATH += $(QUANTUM_PATH)/audio
COMMON_VPATH += $(QUANTUM_PATH)/process_keycode
COMMON_VPATH += $(QUANTUM_PATH)/api
-COMMON_VPATH += $(QUANTUM_PATH)/split_common
COMMON_VPATH += $(DRIVER_PATH)
$(QUANTUM_DIR)/split_common/split_util.c
QUANTUM_LIB_SRC += $(QUANTUM_DIR)/split_common/i2c.c
QUANTUM_LIB_SRC += $(QUANTUM_DIR)/split_common/serial.c
+ COMMON_VPATH += $(QUANTUM_PATH)/split_common
endif