pinctrl: intel: Inline intel_gpio_community_irq_handler()

Since we have for_each_intel_pad_group() helper, there is
no advantage of having intel_gpio_community_irq_handler().
Inline it into intel_gpio_irq().

Acked-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>