pinctrl: intel: Introduce for_each_intel_gpio_group() helper et al.

Introduce a helper macro for_each_intel_gpio_group() et al.
With those in place, update the users.

It reduces the C code base as well as shrinks the binary:

  add/remove: 0/0 grow/shrink: 4/21 up/down: 39/-621 (-582)
  Total: Before=15942, After=15360, chg -3.65%

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