x86/platform/geode: Drop <linux/gpio.h> includes

These board files only use gpio_keys not gpio in general.  This include is
just surplus, delete it.

Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-gpio@vger.kernel.org
Cc: Andres Salomon <dilinger@queued.net>
Cc: linux-geode@lists.infradead.org
Cc: Andy Shevchenko <andy@infradead.org>
Cc: Darren Hart <dvhart@infradead.org>
Cc: platform-driver-x86@vger.kernel.org
Link: https://lkml.kernel.org/r/20190626092119.3172-1-linus.walleij@linaro.org