Use compile_multilib: "both" with "32"/"64" suffixes by default for ART am: 12143d53f2 am: de2b100eb1 am: 042fb6d38c

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

Change-Id: I560bc77034808baf6c88a2f5463f589c39529f4e
Signed-off-by: Automerger Merge Worker <android-build-automerger-merge-worker@system.gserviceaccount.com>