[clang] Fix incorrect array initialization with string literal (fixes #112189) (PR #156846)

[Corentin Jabot via cfe-commits]

cor3ntin wrote:

Thanks for working on this. 

I have some concerns that we do that transformation even in non template contexts, it seems a fairly big hammer. Can you try to find ways to limit how often the cloning is done? id you explore the other suggestion made by @zygoloid at all ? (to do it in TreeTransform)

https://github.com/llvm/llvm-project/pull/156846