pinctrl: samsung: Fix a typo in pinctrl-samsung.h

struct samsung_pin_bank does not have a member called reg_offset.
It should be pctl_offset instead.
Signed-off-by: Sachin Kamat <sachin.kamat@linaro.org>
Acked-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Kukjin Kim <kgene.kim@samsung.com>

drivers/pinctrl/pinctrl-samsung.h

@@ -104,7 +104,7 @@ struct samsung_pinctrl_drv_data;
 
 /**
  * struct samsung_pin_bank: represent a controller pin-bank.
- * @reg_offset: starting offset of the pin-bank registers.
+ * @pctl_offset: starting offset of the pin-bank registers.
  * @pin_base: starting pin number of the bank.
  * @nr_pins: number of pins included in this bank.
  * @func_width: width of the function selector bit field.