gpio: xilinx: Do not use gpiochip_get_data() in xgpio_save_regs()

Commit 097d88e94c ("gpio: xilinx: use gpiochip data pointer") replaces
the use of container_of() with gpiochip_get_data(). Unfortunately, the
data pointer is not yet set by the time xgpio_save_regs() is called,
causing a system hang.

Fixes: 097d88e94c ("gpio: xilinx: use gpiochip data pointer")
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>

drivers/gpio/gpio-xilinx.c

@@ -207,7 +207,8 @@ static int xgpio_dir_out(struct gpio_chip *gc, unsigned int gpio, int val)
  */
 static void xgpio_save_regs(struct of_mm_gpio_chip *mm_gc)
 {
-	struct xgpio_instance *chip = gpiochip_get_data(&mm_gc->gc);
+	struct xgpio_instance *chip =
+		container_of(mm_gc, struct xgpio_instance, mmchip);
 
 	xgpio_writereg(mm_gc->regs + XGPIO_DATA_OFFSET,	chip->gpio_state[0]);
 	xgpio_writereg(mm_gc->regs + XGPIO_TRI_OFFSET, chip->gpio_dir[0]);