Update git submodules

* Update docs/submodules/samplevnf from branch 'master'
  - Merge "Adjusted referencing for docs"
  - Adjusted referencing for docs

    Change-Id: If9e92a2404214e91c682793622f097e28c11597d
    Signed-off-by: Sofia Wallin <sofia.wallin@ericsson.com>

diff --git a/docs/submodules/samplevnf b/docs/submodules/samplevnf
index 3ce13d6..19a44fc 160000 (submodule)
--- a/docs/submodules/samplevnf
+++ b/docs/submodules/samplevnf
@@ -1 +1 @@
-Subproject commit 3ce13d63855abc7d6221cdd1326c551e49ac81ce
+Subproject commit 19a44fc8dd5c78635625580bcd973b8e43508bb1