[llvm] [Github] Add OpenMP docs to Github docs action (PR #70529)

[Tom Stellard via llvm-commits]

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@@ -125,4 +129,9 @@ jobs:
         run: |
           cmake -B lld-build -GNinja -DCMAKE_BUILD_TYPE=Release -DLLVM_ENABLE_PROJECTS="lld" -DLLVM_ENABLE_SPHINX=ON ./llvm
           TZ=UTC ninja -C lld-build docs-lld-html
+      - name: Build OpenMP docs
+        if: steps.docs-changed-subprojects.outputs.openmp_any_changed == 'true'
+        run: |
+          cmake -B openmp-build -GNinja -DCMAKE_BUILD_TYPE=Release -DLLVM_ENABLE_PROJECTS="clang;openmp" -DLLVM_ENABLE_SPHINX=ON ./llvm
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tstellar wrote:

Why do we need to enable clang here?

https://github.com/llvm/llvm-project/pull/70529