Remove legacy BACKLIGHT_CUSTOM_DRIVER option (#13731)

common_features.mk

@@ -363,11 +363,6 @@ ifeq ($(strip $(LCD_ENABLE)), yes)
     CIE1931_CURVE := yes
 endif
 
-# backward compat
-ifeq ($(strip $(BACKLIGHT_CUSTOM_DRIVER)), yes)
-    BACKLIGHT_DRIVER := custom
-endif
-
 VALID_BACKLIGHT_TYPES := pwm timer software custom
 
 BACKLIGHT_ENABLE ?= no

keyboards/jj40/keymaps/oscillope/rules.mk

@@ -6,9 +6,6 @@ CONSOLE_ENABLE = no
 COMMAND_ENABLE = yes
 
 BACKLIGHT_ENABLE = no
-BACKLIGHT_CUSTOM_DRIVER = no
-
 RGBLIGHT_ENABLE = no
-RGBLIGHT_CUSTOM_DRIVER = no
 
 KEY_LOCK_ENABLE = yes

keyboards/meira/rules.mk

@@ -28,7 +28,7 @@ UNICODE_ENABLE = no         # Unicode
 BLUETOOTH_ENABLE = no       # Enable Bluetooth with the Adafruit EZ-Key HID
 AUDIO_ENABLE = no           # Audio output on port C6
 RGBLIGHT_ENABLE = no       # Enable WS2812 RGB underlight.
-BACKLIGHT_CUSTOM_DRIVER = yes
+BACKLIGHT_DRIVER = custom
 BACKLIGHT_ENABLE = yes       # Enable keyboard backlight functionality, also set ISSI_ENABLE below for Miera
 ISSI_ENABLE = yes			# If the I2C pullup resistors aren't install this must be disabled
 

show_options.mk

@@ -16,7 +16,7 @@ BUILD_OPTION_NAMES = \
 HARDWARE_OPTION_NAMES = \
   SLEEP_LED_ENABLE \
   BACKLIGHT_ENABLE \
-  BACKLIGHT_CUSTOM_DRIVER \
+  BACKLIGHT_DRIVER \
   RGBLIGHT_ENABLE \
   RGBLIGHT_CUSTOM_DRIVER \
   RGB_MATRIX_ENABLE \