Update to include ISPC. By Dmitry Babokin.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/branches/release_35@216760 91177308-0d34-0410-b5e6-96231b3b80d8
Include blurb about Likely. By Josh Klontz.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/branches/release_35@216762 91177308-0d34-0410-b5e6-96231b3b80d8
Merge remote-tracking branch 'upstream/release_35' into fabric-3.5