s5pc1xx: gpio: bug fix at gpio_set_pull function

When set to PULL_NONE, gpio_set_pull function is returned without write the register.
This patch fixed it.
Signed-off-by: NMinkyu Kang <mk7.kang@samsung.com>

drivers/gpio/s5p_gpio.c

@@ -96,7 +96,7 @@ void gpio_set_pull(struct s5p_gpio_bank *bank, int gpio, int mode)
 		value |= PULL_MODE(gpio, mode);
 		break;
 	default:
-		return;
+		break;
 	}
 
 	writel(value, &bank->pull);