[ARM] pxa: update pwm_backlight->notify() to include missed 'struct device *'

Signed-off-by: Eric Miao <eric.y.miao@gmail.com>
diff --git a/arch/arm/mach-pxa/magician.c b/arch/arm/mach-pxa/magician.c
index 8a38d60..189f330 100644
--- a/arch/arm/mach-pxa/magician.c
+++ b/arch/arm/mach-pxa/magician.c
@@ -381,7 +381,7 @@
 	return ret;
 }
 
-static int magician_backlight_notify(int brightness)
+static int magician_backlight_notify(struct device *dev, int brightness)
 {
 	gpio_set_value(EGPIO_MAGICIAN_BL_POWER, brightness);
 	if (brightness >= 200) {