platform/x86: oaktrail: Use backlight power constants

Replace FB_BLANK_ constants with their counterparts from the
backlight subsystem. The values are identical, so there's no
change in functionality or semantics.

Signed-off-by: Thomas Zimmermann <[e-mail]>
Cc: Hans de Goede <[e-mail]>
Cc: "Ilpo Järvinen" <[e-mail]>
Link: https://lore.kernel.org/r/[e-mail]
Reviewed-by: Hans de Goede <[e-mail]>
Signed-off-by: Hans de Goede <[e-mail]>

drivers/platform/x86/intel/oaktrail.c

···
 #include <linux/backlight.h>
 #include <linux/dmi.h>
 #include <linux/err.h>
-#include <linux/fb.h>
 #include <linux/i2c.h>
 #include <linux/kernel.h>
 #include <linux/module.h>
···
 	oaktrail_bl_device = bd;
 
 	bd->props.brightness = get_backlight_brightness(bd);
-	bd->props.power = FB_BLANK_UNBLANK;
+	bd->props.power = BACKLIGHT_POWER_ON;
 	backlight_update_status(bd);
 
 	return 0;