Update git submodules

Update git submodules

* Update docs/submodules/netvirt from branch 'master'
  to 6b5cf71d10051548a4115d3569052dd737513fba
  - Enable fingbugs-slf4j enforcement in binding-parent

    This ensures we won’t have any regressions in log handling in modules
    based on binding-parent. We will update the dependency on odlparent
    once the 3.0.3 or 3.1.0 release is available.

    Change-Id: I91f21504c9a18580733a1eedd3ba379de79d37c2
    Signed-off-by: Stephen Kitt <skitt@redhat.com>
  - Fix logging issues in sfc

    Change-Id: I251aafafc48dd3b52de968750869c3ac3253d347
    Signed-off-by: Stephen Kitt <skitt@redhat.com>
  - Fix logging issues in vpnmanager

    Change-Id: I06ada5f51eb2afcdfaa9516a7943a4962dc3f7ca
    Signed-off-by: Stephen Kitt <skitt@redhat.com>