ANDROID: ABI: add initial KMI

Add the initial abi_gki_aarch64.stg ABI representation file to enable
the KMI enforcement on this branch. This file was generated through the
following commands:

  $ touch common/android/abi_gki_aarch64.stg
  $ tools/bazel run //common:kernel_aarch64_abi_nodiff_update

Bug: 325284788
Change-Id: Ie236a80fd49bc04749900ef73890368237ef4236
Signed-off-by: Carlos Llamas <[email protected]>

Author: Carlos Llamas