gpiolib: Fix typo in comment ("piochip_add_data")

Signed-off-by: Jonathan Neuschäfer <j.neuschaefer@gmx.net>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>

drivers/gpio/gpiolib.c

@@ -1374,7 +1374,7 @@ static int devm_gpio_chip_match(struct device *dev, void *res, void *data)
 }
 
 /**
- * devm_gpiochip_add_data() - Resource manager piochip_add_data()
+ * devm_gpiochip_add_data() - Resource manager gpiochip_add_data()
  * @dev: the device pointer on which irq_chip belongs to.
  * @chip: the chip to register, with chip->base initialized
  * @data: driver-private data associated with this chip