Update prebuilt Clang to r510928 (18.0.0). am: 878f994050 am: 7d24122e8c

Original change: https://android-review.googlesource.com/c/platform/prebuilts/clang/host/darwin-x86/+/2871685

Change-Id: I86a5049f540a2daef359fe2f87fcf5b0077e8fa5
Signed-off-by: Automerger Merge Worker <android-build-automerger-merge-worker@system.gserviceaccount.com>