[lldb] [libunwind] [clang] [mlir] [libcxx] [clang-tools-extra] [libcxxabi] [lld] [libc] [openmp] [llvm] [flang] [Clang][Sema] Don't say "is declared here" for invalid template locations (PR #71264)

[Erich Keane via cfe-commits]

https://github.com/erichkeane approved this pull request.

I think this is a very positive change, and see nothing besides Aaron's nit to comment on.  Thanks!

https://github.com/llvm/llvm-project/pull/71264