Copy stable/9 to releng/9.3 as part of the 9.3-RELEASE cycle.

Approved by: re (implicit)
Sponsored by: The FreeBSD Foundation

MFC r244628:

Upgrade our copy of llvm/clang to 3.2 release.

Release notes for llvm:
http://llvm.org/releases/3.2/docs/ReleaseNotes.html

Release notes for clang:
http://llvm.org/releases/3.2/tools/clang/docs/ReleaseNotes.html

Copy head to stable/9 as part of 9.0-RELEASE release cycle.

Approved by: re (implicit)

Import the build makefiles for clang/LLVM.

Approved by: ed (mentor)