hmt: adjust for new pwm_backlight->notify prototype

Commit cfc38999f (backlight: Pass device through notify callback)
added a struct device argument to the notify callback, but didn't
update the user of it in mach-hmt.c
Signed-off-by: NPeter Korsgaard <jacmet@sunsite.dk>
Signed-off-by: NBen Dooks <ben-linux@fluff.org>

arch/arm/mach-s3c6410/mach-hmt.c

@@ -82,7 +82,7 @@ static int hmt_bl_init(struct device *dev)
 	return ret;
 }
 
-static int hmt_bl_notify(int brightness)
+static int hmt_bl_notify(struct device *dev, int brightness)
 {
 	/*
 	 * translate from CIELUV/CIELAB L*->brightness, E.G. from