pinctrl: lewisburg: Replace acpi.h with mod_devicetable.h

There is no need to include acpi.h since driver doesn't use anything from it
except the propagation of mod_devicetable.h.

Include latter directly instead.

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