linaro_swr: Make it a 64bit only build target am: ab68f0ee84 am: d6f5ed0e21

Original change: https://android-review.googlesource.com/c/device/linaro/dragonboard/+/2785579

Change-Id: I6cbbbd611334696c6f7b91006c5b3cfb7f26b89a
Signed-off-by: Automerger Merge Worker <android-build-automerger-merge-worker@system.gserviceaccount.com>