[flang][OpenMP] Skip default privatization for crashing cases (#71922)

This patch skips default privatization for crashing cases like
namelists, reduction instrinsics, and structure constructor.

Fixes: https://github.com/llvm/llvm-project/issues/67332,
https://github.com/llvm/llvm-project/issues/66454, and
https://github.com/llvm/llvm-project/issues/65569



Co-Authored-By: kiranchandramohan <kiran.chandramohan@arm.com>