[www-scripts] Clang Attribute Doc Update: ERROR

[root via www-scripts]

UPDATING LLVM SOURCES
HEAD is now at 18432be [Driver]: fix compiler-rt path when printing libgcc for baremetal
>From https://github.com/llvm/llvm-project
 * branch            master     -> FETCH_HEAD
   18432be..42e89ab  master     -> origin/master
First, rewinding head to replay your work on top of it...
Fast-forwarded master to 42e89ab2a668c80449a13210f07a50fe0370e99d.
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!