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/acpi/video.c b/drivers/acpi/video.c
index 00d25b3..7fd672a 100644
--- a/drivers/acpi/video.c
+++ b/drivers/acpi/video.c
@@ -278,7 +278,7 @@
 {
 	unsigned long cur_level;
 	struct acpi_video_device *vd =
-		(struct acpi_video_device *)class_get_devdata(&bd->class_dev);
+		(struct acpi_video_device *)bl_get_data(bd);
 	acpi_video_device_lcd_get_level_current(vd, &cur_level);
 	return (int) cur_level;
 }
@@ -287,7 +287,7 @@
 {
 	int request_level = bd->props.brightness;
 	struct acpi_video_device *vd =
-		(struct acpi_video_device *)class_get_devdata(&bd->class_dev);
+		(struct acpi_video_device *)bl_get_data(bd);
 	acpi_video_device_lcd_set_level(vd, request_level);
 	return 0;
 }