gpio-lynxpoint: Add X86 dependency and io-port handling header.

Lynxpoint gpio driver uses X86 specific io-ports to control gpios

Signed-off-by: Mathias Nyman <mathias.nyman@linux.intel.com>
Reviewed-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>