ANDROID: GKI: fix mode of android/abi_gki_aarch64.xml file

Somehow the android/abi_gki_aarch64.xml file became executable in a
previous commit.  Fix this up by setting the mode properly.

Bug: 149040612
Cc: Chun-Hung Wu <chun-hung.wu@mediatek.com>
Cc: Sandeep Patil <sspatil@google.com>
Fixes: 55d7c4ec ("ANDROID: Update symbol list for mtk")
Signed-off-by: Greg Kroah-Hartman <gregkh@google.com>
Change-Id: Iecb61df3481cf2a257d2f999297a98cdbcb38295