[clang] [Clang][OpenMP] Fixed an assertion on omp taskloop transparent (PR #200663)

[Oliver Hunt via cfe-commits]

ojhunt wrote:

Adding @kevinsala and @zahiraam as they've touched this file a bunch of times and a few omp folk looking at this seems best as I'm not sure Corentin, Aaron, or I have the requisite knowledge to confirm that this change is correct.

https://github.com/llvm/llvm-project/pull/200663