Fix lifetimebound for field access (llvm#100197)

Fixes: llvm#81589

There is no way to switch this off without  `-Wno-dangling`.

Author: usx95

clang/docs/ReleaseNotes.rst

@@ -132,6 +132,9 @@ Improvements to Clang's diagnostics
 
 - Clang now diagnoses undefined behavior in constant expressions more consistently. This includes invalid shifts, and signed overflow in arithmetic.
 
+- Clang now diagnoses dangling references to fields of temporary objects. Fixes #GH81589.
+
+
 Improvements to Clang's time-trace
 ----------------------------------