[www-scripts] Clang Attribute Doc Update: ERROR

[root via www-scripts]

UPDATING LLVM SOURCES
HEAD is now at 2c65908 [AMDGPU] Don't combine memory intrs to v3i16
>From https://github.com/llvm/llvm-project
 * branch            master     -> FETCH_HEAD
   2c65908..3520297  master     -> origin/master
First, rewinding head to replay your work on top of it...
Fast-forwarded master to 3520297039d69381cb5776235209fc08863b9095.
CMake Error at CMakeLists.txt:6 (message):
  Your CMake version is 3.7.1.  The minimum version of CMake required to
  build LLVM is now 3.13.4.


-- Configuring incomplete, errors occurred!