leds: tca6507: use gpiochip data pointer

This makes the driver use the data pointer added to the gpio_chip
to store a pointer to the state container instead of relying on
container_of().

Cc: Riku Voipio <riku.voipio@iki.fi>
Cc: Richard Purdie <rpurdie@rpsys.net>
Cc: linux-leds@vger.kernel.org
Acked-by: Jacek Anaszewski <j.anaszewski@samsung.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>

drivers/leds/leds-tca6507.c

@@ -603,7 +603,7 @@ static int tca6507_blink_set(struct led_classdev *led_cdev,
 static void tca6507_gpio_set_value(struct gpio_chip *gc,
 				   unsigned offset, int val)
 {
-	struct tca6507_chip *tca = container_of(gc, struct tca6507_chip, gpio);
+	struct tca6507_chip *tca = gpiochip_get_data(gc);
 	unsigned long flags;
 
 	spin_lock_irqsave(&tca->lock, flags);
@@ -655,7 +655,7 @@ static int tca6507_probe_gpios(struct i2c_client *client,
 #ifdef CONFIG_OF_GPIO
 	tca->gpio.of_node = of_node_get(client->dev.of_node);
 #endif
-	err = gpiochip_add(&tca->gpio);
+	err = gpiochip_add_data(&tca->gpio, tca);
 	if (err) {
 		tca->gpio.ngpio = 0;
 		return err;