Update git submodules

* Update docs/submodules/sdnvpn from branch 'stable/fraser'
  - Add own logger for SdnvpnFuncTest class

    The functest xtesting Testcase class removed the logger instance
    variable, so let SdnvpnFuncTest use its own logger.

    JIRA: SDNVPN-215

    Change-Id: I8b611273e44204d5051fad1140e6ecaddc2a4334
    Signed-off-by: Periyasamy Palanisamy <periyasamy.palanisamy@ericsson.com>
    (cherry picked from commit 6491326ffadcc143a64723169038cad58620f117)

diff --git a/docs/submodules/sdnvpn b/docs/submodules/sdnvpn
index e0a0bcc..a239b4b 160000 (submodule)
--- a/docs/submodules/sdnvpn
+++ b/docs/submodules/sdnvpn
@@ -1 +1 @@
-Subproject commit e0a0bccf7172b8cdd3e0ac2af7c2736b89ef5f75
+Subproject commit a239b4b3be5e21c522b3f189f3e3f7246e15630f