[www-scripts] Clang Attribute Doc Update: ERROR

[root via www-scripts]

UPDATING LLVM SOURCES
HEAD is now at bebe6a6 [GlobalISel] Combine (logic_op (op x...), (op y...)) -> (op (logic_op x, y))
>From https://github.com/llvm/llvm-project
 * branch            master     -> FETCH_HEAD
   bebe6a6..61afdf0  master     -> origin/master
First, rewinding head to replay your work on top of it...
Fast-forwarded master to 61afdf0ab43f1aec93d3d482cd3d1d95c537aefe.
CMake Error at CMakeLists.txt:3 (cmake_minimum_required):
  CMake 3.13.4 or higher is required.  You are running version 3.7.1


-- Configuring incomplete, errors occurred!