Update git submodules

* Update docs/submodules/ovn4nfv from branch 'stable/fraser'
  - OVN4NFV Fraser 6.2.0 release notes.

    Change-Id: I85781832e4e7d5fe66d9da1766f99dbd18c3dd54
    Signed-off-by: Trinath Somanchi <trinath.somanchi@nxp.com>
    (cherry picked from commit fbec8835ec57be01834b7b5ec4283346ab54bc12)

diff --git a/docs/submodules/ovn4nfv b/docs/submodules/ovn4nfv
index 651acb6..1d7faee 160000 (submodule)
--- a/docs/submodules/ovn4nfv
+++ b/docs/submodules/ovn4nfv
@@ -1 +1 @@
-Subproject commit 651acb603c2f4523905e4fe5134fd8a7940e1f3d
+Subproject commit 1d7faee41c361aeebf78a6d514587eae50e916f7