gpio: mm-lantiq: Do not use gpiochip_get_data() in ltq_mm_save_regs()

Commit 6aa7dbfa2877 ("gpio: mm-lantiq: use gpiochip data pointer") replaces
the use of container_of() with gpiochip_get_data(). However, the data
pointer is not yet set by the time the save_regs function is called.

Fixes: 6aa7dbfa2877 ("gpio: mm-lantiq: use gpiochip data pointer")
Cc: Ricardo Ribalda Delgado <ricardo.ribalda@gmail.com>
Cc: John Crispin <blogic@openwrt.org>
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
diff --git a/drivers/gpio/gpio-mm-lantiq.c b/drivers/gpio/gpio-mm-lantiq.c
index a2071ed..54e5d82 100644
--- a/drivers/gpio/gpio-mm-lantiq.c
+++ b/drivers/gpio/gpio-mm-lantiq.c
@@ -91,7 +91,8 @@
  */
 static void ltq_mm_save_regs(struct of_mm_gpio_chip *mm_gc)
 {
-	struct ltq_mm *chip = gpiochip_get_data(&mm_gc->gc);
+	struct ltq_mm *chip =
+		container_of(mm_gc, struct ltq_mm, mmchip);
 
 	/* tell the ebu controller which memory address we will be using */
 	ltq_ebu_w32(CPHYSADDR(chip->mmchip.regs) | 0x1, LTQ_EBU_ADDRSEL1);