[clang] [Clang][test] Use `-fopenmp=libomp` explicitly for amdgpu-unwind.cl (PR #198821)

[Matt Arsenault via cfe-commits]

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@@ -3,22 +3,22 @@
 // Default options
 // RUN: %clang -### -x cl --target=amdgcn-amd-amdhsa -c -emit-llvm --no-offloadlib -nogpuinc %s 2>&1 | FileCheck -check-prefix=ASYNC-TABLES %s
 // RUN: %clang -### -x hip --offload-arch=gfx90a --offload-device-only --no-offloadlib -c -emit-llvm -nogpuinc %s 2>&1 | FileCheck -check-prefix=ASYNC-TABLES  %s
-// RUN: %clang -### -fopenmp --offload-arch=gfx90a --offload-device-only --no-offloadlib -c -emit-llvm -nogpuinc %s 2>&1 | FileCheck -check-prefix=ASYNC-TABLES  %s
+// RUN: %clang -### -fopenmp=libomp --offload-arch=gfx90a --offload-device-only --no-offloadlib -c -emit-llvm -nogpuinc %s 2>&1 | FileCheck -check-prefix=ASYNC-TABLES  %s
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arsenm wrote:

I don't understand why this test is using -fopenmp with OpenCL. The combination doesn't make sense 

https://github.com/llvm/llvm-project/pull/198821