[clang] [CIR][OpenMP] Implement lowering for the 'num_threads' clause for 'parallel' directive (PR #202466)

[Jan Leyonberg via cfe-commits]

jsjodin wrote:

#201592 was merged now, so you can use the integer cast op instead of the unrealized cast op.

https://github.com/llvm/llvm-project/pull/202466