mfd: arizona: Replace arizona_of_get_type() with device_get_match_data()

Replace the custom arizona_of_get_type() function with the generic
device_get_match_data() helper. Besides being a nice cleanup this
also makes it easier to add support for binding to ACPI enumerated
devices.

While at it also fix a possible NULL pointer deref of the id
argument to the probe functions (this could happen on e.g. manual
driver binding through sysfs).

Suggested-by: Andy Shevchenko <andy.shevchenko@gmail.com>
Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com>
Acked-by: Charles Keepax <ckeepax@opensource.cirrus.com>
Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Signed-off-by: Lee Jones <lee.jones@linaro.org>