Merge "Make vendor_ramdisk_available." am: 20d5f807a7 am: 6c49ee654c am: 1ab23e7c3d

Original change: https://android-review.googlesource.com/c/platform/external/libunwind_llvm/+/1475076

Change-Id: I4222d1985333fe2a6c95ae16cb90737dd13e7177