Merge "Revert "Add rv64 prebuilts directly from the toolchain."" into main am: 9f4bf52ac0 am: 0212581349 am: fb9c733ec8 am: 1f13386dd0

Original change: https://android-review.googlesource.com/c/platform/prebuilts/ndk/+/2676817

Change-Id: Ic7129631ab79e0a08517726b720d42686a3ee994
Signed-off-by: Automerger Merge Worker <android-build-automerger-merge-worker@system.gserviceaccount.com>