Bring the contrib/llvm/patches directory up-to-date for stable/9.

Bring the contrib/llvm/patches directory up-to-date for stable/9.

MFC r263892:
Add the llvm/clang patch for r263891.

MFC r264350:
Update the llvm/clang patch for r264345.

MFC r264828:
Add patches corresponding to r264826 and r264827

MFC r266630:
Add the clang patch for r265477.  While here, add a description to the
patch for r263619, and unify all the URLs to point to svnweb.

MFC r266675:
Add the clang patch for r266674.

MFC r275651:
Add llvm patch corresponding to r275633.

MFC r275747:
Update llvm patches for r274286 and r275633 so all the tests will pass.

MFC r275760:
Add clang patch corresponding to r275759.

MFC r275772:
Update clang patch for r275759 to use correct test cases.

MFC r283015:
Bring the contrib/llvm/patches directory up-to-date.

MFC r263892:
Add the llvm/clang patch for r263891.

MFC r264350:
Update the llvm/clang patch for r264345.

MFC r266675:
Add the clang patch for r266674.

MFC r275651:
Add llvm patch corresponding to r275633.

MFC r275747:
Update llvm patches for r274286 and r275633 so all the tests will pass.

MFC r275760:
Add clang patch corresponding to r275759.

MFC r275772:
Update clang patch for r275759 to use correct test cases.

Partially merge r283015 from stable/10:
Additionally:
* Remove the clang patch corresponding to r263619, as ARM EABI
  hard-float support was never MFC'd.
* Add clang patch corresponding to r279302.

git-svn-id: svn://svn.freebsd.org/base/stable/9@283020 ccf9f872-aa2e-dd11-9fc8-001c23d0bc1f