cmake: address new warnings from cmake-3.17

Match package-name case from CMakeLists.txt .

New warning sample:

    The package name passed to `find_package_handle_standard_args` (LLVM) does
    not match the name of the calling package (llvm).  This can lead to
    problems in calling code that expects `find_package` result variables
    (e.g., `_FOUND`) to follow a certain pattern.