Add credit and release notes for r150307. By Kai Nacke.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@154796 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/docs/ReleaseNotes.html b/docs/ReleaseNotes.html
index 1723576..aa85e15 100644
--- a/docs/ReleaseNotes.html
+++ b/docs/ReleaseNotes.html
@@ -400,6 +400,7 @@
   times and better support for different calling conventions.  The old WINCALL
   instructions are no longer needed.</li>
   <li>DW2 Exception Handling is enabled on Cygwin and MinGW.</li>
+  <li>Support for implicit TLS model used with MS VC runtime</li>
 </ul>
 
 </div>