[CMake][Release] Use the TXZ cpack generator for binaries (llvm#90138)

Author: tstellar

.github/workflows/release-binaries.yml

@@ -214,7 +214,7 @@ jobs:
 
     - id: package-info
       run: |
-        filename="LLVM-${{ needs.prepare.outputs.release-version }}-Linux.tar.gz"
+        filename="LLVM-${{ needs.prepare.outputs.release-version }}-Linux.tar.xz"
         echo "filename=$filename" >> $GITHUB_OUTPUT
         echo "path=/mnt/build/tools/clang/stage2-bins/$filename" >> $GITHUB_OUTPUT
 

clang/cmake/caches/Release.cmake

@@ -91,4 +91,6 @@ endif()
 # Final Stage Config (stage2)
 set_final_stage_var(LLVM_ENABLE_RUNTIMES "${LLVM_RELEASE_ENABLE_RUNTIMES}" STRING)
 set_final_stage_var(LLVM_ENABLE_PROJECTS "${LLVM_RELEASE_ENABLE_PROJECTS}" STRING)
+set_final_stage_var(CPACK_GENERATOR "TXZ" STRING)
+set_final_stage_var(CPACK_ARCHIVE_THREADS "0" STRING)