[clang] [clang][Interp] Fix `ArrayInitLoopExpr` handling (PR #67886)

[Timm Baeder via cfe-commits]

tbaederr wrote:

Sorry, but I had to investigate this locally anyway because the opaque value test started to break with one of my patches from today. I came up with https://github.com/llvm/llvm-project/commit/b4fc1418d9765bfb605387efc70ecf233d27b383. Thanks for your work on this though.

https://github.com/llvm/llvm-project/pull/67886