pinctrl/broxton: enable platform device in the absence of ACPI enumeration

This is to cater the need for non-ACPI system whereby
a platform device has to be created in order to bind
with the Apollo Lake Pinctrl GPIO platform driver.

Signed-off-by: Tan Jui Nee <jui.nee.tan@intel.com>
Acked-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>