llvm-devel CMake broken

[aengelke]

The typical LLVM-install CMake problem... llvm-devel should depend on clang-tools-extra, similar to the other packages as per the comment in the build file.

CMake Error at /usr/lib/cmake/llvm/LLVMExports.cmake:1780 (message):
  The imported target "sancov" references the file

     "/usr/bin/sancov"

  but this file does not exist.

Actually, someone(TM) should adjust CMake to not blindly require all files to exist. :\