[llvm] [Offload] Add CMake cache to be used in AMDGPU bot (PR #119369)

[Shilei Tian via llvm-commits]

================
@@ -0,0 +1,13 @@
+set(LLVM_ENABLE_PROJECTS "clang;lld" CACHE STRING "")
+set(LLVM_ENABLE_RUNTIMES "compiler-rt;openmp;offload" CACHE STRING "")
+set(LLVM_ENABLE_PER_TARGET_RUNTIME_DIR ON CACHE BOOL "")
+set(LLVM_ENABLE_ASSERTIONS ON CACHE BOOL "")
+set(LLVM_LIT_ARGS "-v --show-unsupported --timeout 100 --show-xfail -j 32" CACHE STRING "")
+set(LLVM_TARGETS_TO_BUILD "X86;AMDGPU" CACHE STRING "")
+
+set(CLANG_DEFAULT_LINKER "lld" CACHE STRING "")
+
+set(CMAKE_INSTALL_PREFIX /tmp/llvm.install.jpbot CACHE STRING "")
----------------
shiltian wrote:

If this file is purely for testing, I'd add the document to the beginning of this file; otherwise it doesn't make sense to me to force this.

https://github.com/llvm/llvm-project/pull/119369