gpio: rc5t583: Remove redundant check

Variable "offset" cannot be negative, so no need to check if it
greater than zero or equal.

Signed-off-by: Alexander Shiyan <[e-mail]>
Signed-off-by: Linus Walleij <[e-mail]>

drivers/gpio/gpio-rc5t583.c

···
 {
 	struct rc5t583_gpio *rc5t583_gpio = to_rc5t583_gpio(gc);
 
-	if ((offset >= 0) && (offset < 8))
+	if (offset < RC5T583_MAX_GPIO)
 		return rc5t583_gpio->rc5t583->irq_base +
 				RC5T583_IRQ_GPIO0 + offset;
 	return -EINVAL;