[clang] [Clang] Generate the GEP instead of adding AST nodes (PR #73730)

[Bill Wendling via cfe-commits]

bwendling wrote:

@AaronBallman It's not letting me comment on your comment. While a compound literal doesn't have a DRE, it's also not a flexible array, so it's not supposed to get this far.

https://github.com/llvm/llvm-project/pull/73730