[clang] [openmp] [Clang][OpenMP] Fix mapping of structs to device (PR #75642)

[Joseph Huber via cfe-commits]

jhuber6 wrote:

> This fails for me on the host and the AMD GPU: GPU:
> 
> ```
> # | <stdin>:217:1: note: possible intended match here
> # | dat.datum[dat.arr[0][0]] = 5
> ```
> 
> X86:
> 
> ```
> # | <stdin>:134:1: note: possible intended match here
> # | dat.datum[dat.arr[0][0]] = 5461
> ```
> 
> The location that is printed (datum[1]) is uninitialized.

I see the same but forgot to say anything.

https://github.com/llvm/llvm-project/pull/75642