ANDROID: GKI: add abi_gki_aarch64_galaxy

Add initial abi_gki_aarch64_galaxy file, with no new symbols being
needed, they will be added later.

Bug: 166527556
Change-Id: I09a44ce129fc8d689150303887d5ba6c5e2bffce
Signed-off-by: Jungrae Kim <jryu.kim@samsung.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@google.com>