pinctrl: baytrail: Drop no-op ACPI_PTR() call

Since we dependent on ACPI, there is no need to use ACPI_PTR()
which is a no-op in this case.

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