[libclc] [libclc] Fix commands in compile_to_bc are executed sequentially (PR #130755)

[Wenju He via cfe-commits]

wenju-he wrote:

@frasercrmck should we check CMAKE_VERSION and use DEPENDS_EXPLICIT_ONLY if the version is 3.27 or higher? I suppose DEPENDS_EXPLICIT_ONLY would be more light-weighted. And we need to keep both DEPENDS_EXPLICIT_ONLY and adding new target path, until llvm uplifts cmake version to 3.27.

https://github.com/llvm/llvm-project/pull/130755