Running 'python3 update.py linux' from 'third_party/llvm-7.0/scripts/'
Also includes common config changes for LLVM 7.0.1 release.

Bug chromium:944811

Change-Id: I22dadbe6024a0e46707361abc92630381de12ad6
Reviewed-on: https://swiftshader-review.googlesource.com/c/SwiftShader/+/27871Tested-by: Nicolas Capens <nicolascapens@google.com>
Presubmit-Ready: Nicolas Capens <nicolascapens@google.com>
Reviewed-by: Alexis Hétu <sugoi@google.com>
Kokoro-Presubmit: kokoro <noreply+kokoro@google.com>