backlight: Add backlight_device parameter to check_fb

check_fb from backlight_ops lacks a reference to the backlight_device
that's being referred to. Add this parameter so a backlight_device
can be mapped to a single framebuffer, especially if the same driver
handles multiple devices on a single system.

Signed-off-by: Bruno Prémont <bonbons@linux-vserver.org>
Signed-off-by: Richard Purdie <rpurdie@linux.intel.com>
diff --git a/include/linux/backlight.h b/include/linux/backlight.h
index ee377d7..21cd866 100644
--- a/include/linux/backlight.h
+++ b/include/linux/backlight.h
@@ -47,7 +47,7 @@
 	int (*get_brightness)(struct backlight_device *);
 	/* Check if given framebuffer device is the one bound to this backlight;
 	   return 0 if not, !=0 if it is. If NULL, backlight always matches the fb. */
-	int (*check_fb)(struct fb_info *);
+	int (*check_fb)(struct backlight_device *, struct fb_info *);
 };
 
 /* This structure defines all the properties of a backlight */