backlight: Convert from struct class_device to struct device

Convert the backlight and LCD classes from struct class_device
to struct device since class_device is scheduled for removal.

One nasty API break is the backlight power attribute has had to be
renamed to bl_power and the LCD power attribute has had to be renamed
to lcd_power since the original names clash with the core. I can't see
a way around this.

Signed-off-by: Richard Purdie <rpurdie@rpsys.net>
Acked-by: Greg Kroah-Hartman <gregkh@suse.de>
diff --git a/drivers/video/aty/atyfb_base.c b/drivers/video/aty/atyfb_base.c
index 2fbff63..d2c68c3 100644
--- a/drivers/video/aty/atyfb_base.c
+++ b/drivers/video/aty/atyfb_base.c
@@ -2141,7 +2141,7 @@
 
 static int aty_bl_update_status(struct backlight_device *bd)
 {
-	struct atyfb_par *par = class_get_devdata(&bd->class_dev);
+	struct atyfb_par *par = bl_get_data(bd);
 	unsigned int reg = aty_ld_lcd(LCD_MISC_CNTL, par);
 	int level;