platform/x86: x86-android-tablets: Add support for instantiating serdevs

Add support for instantiating serdevs, this is necessary on some boards
where the serdev info in the DSDT has issues.

Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Link: https://lore.kernel.org/r/20211229231431.437982-8-hdegoede@redhat.com