[clang] [llvm] [UBSan] make ubsantrap `inaccessiblemem: write` (PR #156100)

[Florian Mayer via llvm-commits]

fmayer wrote:

> LGTM, assuming the intended usage model for these does not include introspection of memory at the time of trap.

Not more or less than a normal `builtin_trap()`. Someone might look at it in a debugger, or look at the crash stack trace.

https://github.com/llvm/llvm-project/pull/156100