protocols.mk is already included in latest QMK

keyboards/handwired/promethium/rules.mk

@@ -70,6 +70,5 @@ PS2_USE_INT ?= yes
 # Do not enable SLEEP_LED_ENABLE. it uses the same timer as BACKLIGHT_ENABLE
 SLEEP_LED_ENABLE ?= no    # Breathing sleep LED during USB suspend
 
-include $(TMK_DIR)/protocol.mk
 SRC += $(QUANTUM_DIR)/light_ws2812.c
 SRC += rgbsps.c