Update git submodules

Update git submodules

* Update docs/submodules/functest from branch 'master'
  - Merge "Remove the former link /home/opnfv/repos/functest"
  - Remove the former link /home/opnfv/repos/functest

    All operations required have been applied [1].

    All documentations are updated as well to close the topic.
    It should be noted that runfunctest.rst must be hugely updated
    because all $PS1 are wrong.

    [1] https://gerrit.opnfv.org/gerrit/#/q/project:functest+branch:master+topic:dockerfile

    JIRA: FUNCTEST-836

    Change-Id: I26658be109fd785d068389816be4260cff823705
    Signed-off-by: Cédric Ollivier <cedric.ollivier@orange.com>