Adding OpenMP usage with rocprofv3 (#472)

* Adding openmp usage with rocprofv3

* minor changes

* Fixing missing line

[ROCm/rocprofiler-sdk commit: e7616c3aad]

projects/rocprofiler-sdk/source/docs/_toc.yml.in

@@ -18,6 +18,7 @@ subtrees:
     - file: how-to/using-rocprofv3-avail
     - file: how-to/using-rocprofiler-sdk-roctx
     - file: how-to/using-rocprofv3-with-mpi
+    - file: how-to/using-rocprofv3-with-openmp
     - file: how-to/using-pc-sampling
     - file: how-to/using-thread-trace
   - caption: API reference