[clang] [CIR][OpenMP] Implement lowering for the 'if' clause for 'parallel' d… (PR #204999)

[Sergio Afonso via cfe-commits]

https://github.com/skatrak approved this pull request.

Thank you, this LGTM minus some non-blocking nits.

https://github.com/llvm/llvm-project/pull/204999