[OpenMP] Add Additional Function Attribute Information to OMPKinds.def

Summary:
This patch adds more function attribute information to the runtime function definitions in OMPKinds.def. The goal is to provide sufficient information about OpenMP runtime functions to perform more optimizations on OpenMP code.

Reviewers: jdoerfert

Subscribers: aaron.ballman cfe-commits yaxunl guansong sstefan1 llvm-commits

Tags: #OpenMP #clang #llvm

Differential Revision: https://reviews.llvm.org/D81031