pinctrl: geminilake: Get rid of unneeded ->probe() stub

The local ->probe() stub does nothing except calling
a generic Intel pin control probe function. Thus,
it's not needed and generic function may be called directly.

This patch converts the driver accordingly.

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>