pinctrl: intel: merrifield: Correct UART pin lists

UART pin lists consist GPIO numbers which is simply wrong.
Replace it by pin numbers.

Fixes: 4e80c8f5

 ("pinctrl: intel: Add Intel Merrifield pin controller support")
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Acked-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>