pocl: updated llvm dependency to require not having flang (#22190)
pocl: updated llvm dependency to require not having flang (#22190)

depends_on("llvm +clang +shared_libs -flang @6.0:11.0", when="@1.6")
LLNL/spack,LLNL/spack,LLNL/spack,LLNL/spack,LLNL/spack