x86: quark: acpi: Replace _ADR() by _UID() in description of PCI host bridge

PCI Firmware specification requires _UID() and doesn't require _ADR()
to be set. Replace latter by former. This fixes the following warning
reported by ACPICA 20200430:

  Warning 3073 - Multiple types (Device object requires either a _HID
  or _ADR, but not both)

Signed-off-by: Bin Meng <bmeng.cn@gmail.com>
Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>