[HIP] Add HIP scope atomic operations

Add an AtomicScopeModel for HIP and support for OpenCL builtins
that are missing in HIP.

Patch by: Michael Liao

Revised by: Anshil Ghandi

Reviewed by: Yaxun Liu

Differential Revision: https://reviews.llvm.org/D113925

GitOrigin-RevId: e13246a2ec3dfc13838d43099ca9111c780d2c5e
9 files changed