ReleaseNotes: some notes from Andres Freund

git-svn-id: https://llvm.org/svn/llvm-project/llvm/branches/release_70@341916 91177308-0d34-0410-b5e6-96231b3b80d8

Author: zmodem

docs/ReleaseNotes.rst

@@ -116,6 +116,8 @@ Non-comprehensive list of changes in this release
 * The :program:`opt` tool now supports the ``-load-pass-plugin`` option for
   loading pass plugins for the new PassManager.
 
+* Support for profiling JITed code with perf.
+
 
 Changes to the LLVM IR
 ----------------------
@@ -277,6 +279,9 @@ Changes to the C API
   interface was made a deprecated no-op in LLVM 5. Use
   ``LLVMAddSLPVectorizePass`` instead to get the supported SLP vectorizer.
 
+* Expanded the OrcJIT APIs so they can register event listeners like debuggers
+  and profilers.
+
 Changes to the DAG infrastructure
 ---------------------------------
 * ``ADDC``/``ADDE``/``SUBC``/``SUBE`` are now deprecated and will default to expand. Backends