[llvm] AMDGPU: Ensure both wavesize features are not set (PR #159234)

[LLVM Continuous Integration via llvm-commits]

llvm-ci wrote:

LLVM Buildbot has detected a new failure on builder `ppc64le-flang-rhel-clang` running on `ppc64le-flang-rhel-test` while building `llvm` at step 6 "test-build-unified-tree-check-flang".

Full details are available at: https://lab.llvm.org/buildbot/#/builders/157/builds/40408

<details>
<summary>Here is the relevant piece of the build log for the reference</summary>

```
Step 6 (test-build-unified-tree-check-flang) failure: 1200 seconds without output running [b'ninja', b'check-flang'], attempting to kill
...
PASS: Flang :: Semantics/typeinfo02.f90 (3832 of 3842)
PASS: Flang :: Transforms/debug-omp-target-op-1.fir (3833 of 3842)
PASS: Flang :: Transforms/stack-arrays.f90 (3834 of 3842)
PASS: Flang :: Transforms/debug-line-table.fir (3835 of 3842)
PASS: Flang :: Transforms/tbaa4.fir (3836 of 3842)
PASS: Flang :: Transforms/debug-dwarf-version.fir (3837 of 3842)
PASS: Flang :: Transforms/tbaa-local-alloc-threshold.fir (3838 of 3842)
PASS: Flang :: Lower/OpenMP/rtl-flags.f90 (3839 of 3842)
PASS: Flang :: Driver/omp-driver-offload.f90 (3840 of 3842)
PASS: Flang :: Intrinsics/math-codegen.fir (3841 of 3842)
command timed out: 1200 seconds without output running [b'ninja', b'check-flang'], attempting to kill
process killed by signal 9
program finished with exit code -1
elapsedTime=3413.458535

```

</details>

https://github.com/llvm/llvm-project/pull/159234