[OPENMP] Improve handling of cancel directives in target-based
constructs, NFC.

Improved handling of cancel|cancellation point directives inside
target-based for directives.

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@319046 91177308-0d34-0410-b5e6-96231b3b80d8
3 files changed