fix variable value of rules.mk

keyboards/hhkb/rules.mk

@@ -68,8 +68,8 @@ CUSTOM_MATRIX    ?= yes # Custom matrix file for the HHKB
 # SLEEP_LED_ENABLE ?= yes  # Breathing sleep LED during USB suspend
 # NKRO_ENABLE ?= yes       # USB Nkey Rollover - if this doesn't work, see here: https://github.com/tmk/tmk_keyboard/wiki/FAQ#nkro-doesnt-work
 # BACKLIGHT_ENABLE ?= yes  # Enable keyboard backlight functionality
-# MIDI_ENABLE ?= YES		# MIDI controls
-# UNICODE_ENABLE ?= YES		# Unicode
+# MIDI_ENABLE ?= yes       # MIDI controls
+# UNICODE_ENABLE ?= yes    # Unicode
 # BLUETOOTH_ENABLE ?= yes  # Enable Bluetooth with the Adafruit EZ-Key HID
 
 ifneq (, $(findstring yes, $(HHKB_JP)))