am dd73bf00: Update darwin clang prebuilts to be 64-bit.

* commit 'dd73bf00de3f279e5e4d1b120fe3783bfde20df0':
  Update darwin clang prebuilts to be 64-bit.
tree: 669855f80852f189498361f8de2737e5934553da
  1. bin/
  2. lib/
  3. update.sh