platform/x86: x86-android-tablets: Store serdev-controller ACPI HID + UID in a union

Store the serdev-controller ACPI HID + UID in a union inside struct
x86_serdev_info.

This is a preparation patch for adding support for PCI enumerated serdev-
controllers which will be done by the devfn value of the PCI device.

Reviewed-by: Andy Shevchenko <andy@kernel.org>
Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Link: https://lore.kernel.org/r/20241204204227.95757-7-hdegoede@redhat.com


Reviewed-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>
Signed-off-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>