platform/x86: dell-uart-backlight: Use blacklight power constant

The backlight subsystem has gotten its own power constants. Replace
FB_BLANK_UNBLANK with BACKLIGHT_POWER_ON.

Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de>
Link: https://lore.kernel.org/r/20241213100647.200598-1-tzimmermann@suse.de
Reviewed-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>
Signed-off-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>

drivers/platform/x86/dell/dell-uart-backlight.c

@@ -159,7 +159,7 @@ static int dell_uart_set_bl_power(struct dell_uart_backlight *dell_bl, int power
 
 	set_power[0] = DELL_SOF(SET_CMD_LEN);
 	set_power[1] = CMD_SET_BL_POWER;
-	set_power[2] = (power == FB_BLANK_UNBLANK) ? 1 : 0;
+	set_power[2] = (power == BACKLIGHT_POWER_ON) ? 1 : 0;
 	set_power[3] = dell_uart_checksum(set_power, 3);
 
 	ret = dell_uart_bl_command(dell_bl, set_power, SET_CMD_LEN, resp, SET_RESP_LEN);