Fix broken doc link to Clang 3.5 release notes

We appear to use 3.5.0 in the directory structure now. That's probably
unnecessary. We should probably let the micro releases update the docs
for the same minor version.

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@227127 91177308-0d34-0410-b5e6-96231b3b80d8

docs/ReleaseNotes.rst

@@ -12,7 +12,7 @@ Written by the `LLVM Team <http://llvm.org/>`_
 
    These are in-progress notes for the upcoming Clang 3.7 release. You may
    prefer the `Clang 3.5 Release Notes
-   <http://llvm.org/releases/3.5/tools/clang/docs/ReleaseNotes.html>`_.
+   <http://llvm.org/releases/3.5.0/tools/clang/docs/ReleaseNotes.html>`_.
 
 Introduction
 ============