pinctrl: lynxpoint: Correct amount of pins

When we count from 0 it's possible to get into off-by-one error.
That's what had happened to this driver. So, correct amount of pins
and related typos in the code.

Reviewed-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Acked-by: Mika Westerberg <mika.westerberg@linux.intel.com>