[AMDGPU][Waitcnt] Update a few tests to use default waitcnt pass (si-insert-waitcnts) rather than old pass (si-insert-waits); this is a small step towards the overall goal of removing the old waitcnt pass, which is no longer maintained.

Differential Revision: https://reviews.llvm.org/D46154

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@331062 91177308-0d34-0410-b5e6-96231b3b80d8
4 files changed