[AMDGPU] Test for in-order waitcnt insertion for bvh instructions

In-order bvh instructions don't require a waitcnt as order is
guaranteed.

However, waitcnt IS required for other image instruction types vs
bvh.

Pre-commit test for new functionality in https://reviews.llvm.org/D114794

Differential Revision: https://reviews.llvm.org/D114792