Use compile_multilib: "both" with "32"/"64" suffixes by default for ART am: 12143d53f2

Original change: https://android-review.googlesource.com/c/platform/art/+/2122595

Change-Id: Ie62440d8cb27020ee6e17414424d1cfd83c2ce97
Signed-off-by: Automerger Merge Worker <android-build-automerger-merge-worker@system.gserviceaccount.com>