iio: proximity: sx9500: Add GPIO ACPI mapping table

In order to satisfy GPIO ACPI library requirements convert users of
gpiod_get_index() to correctly behave when there no mapping is provided
by firmware.

Here we add explicit mapping between _CRS GpioIo() resources and
their names used in the driver.

Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>