ARM: sa1100: Open code gpio_request_array()

In order to prerare for removal of gpio_request_array(), open code
the latter. Note, we are not using gpio_request_one() as it's also
deprecated, hence reducing legacy API usage to the very basic ones.

Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Bartosz Golaszewski <bartosz.golaszewski@linaro.org>