[clang] [clang][test][OpenMP] Fix test assumptions of libomp and clang paths (PR #125891)

[Jordan Rupprecht via cfe-commits]

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@@ -1,49 +1,49 @@
 // REQUIRES: x86-registered-target, amdgpu-registered-target
 
 // Fail on invalid ROCm Path.
-// RUN:   not %clang -### --target=x86_64-unknown-linux-gnu -fopenmp --offload-arch=gfx908:xnack+ -fsanitize=address -fgpu-sanitize -nogpuinc --rocm-path=%S/Inputs/rocm-invalid  %s 2>&1 \
+// RUN:   not %clang -no-canonical-prefixes -### --target=x86_64-unknown-linux-gnu -fopenmp=libomp --offload-arch=gfx908:xnack+ -fsanitize=address -fgpu-sanitize -nogpuinc --rocm-path=%S/Inputs/rocm-invalid  %s 2>&1 \
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rupprecht wrote:

The error is: `clang: error: '-fopenmp-targets' must be used in conjunction with a '-fopenmp' option compatible with offloading; e.g., '-fopenmp=libomp' or '-fopenmp=libiomp5' `

The `-fopenmp-targets` flag is not explicitly set here, I assume it must be added somewhere with the driver based on another param.

https://github.com/llvm/llvm-project/pull/125891