Update git submodules

Update git submodules

* Update docs/submodules/releng from branch 'master'
  - Merge "prototypes: xci: Add 'ansible-hardening' role to the requirements file"
  - prototypes: xci: Add 'ansible-hardening' role to the requirements file

    Upstream commit 2798cf403c47d165cd8d34d7888990dce1f827f8 ("Use new
    ansible-hardening role") added the new 'ansible-hardening' role to the
    ansible-role-requirements.yml file and as such we also need to take that
    into consideration. The sha hash does not matter much at this point
    since it will be fixed the next time we tag all the roles.

    Change-Id: I5444af948e2b83de49863e7e28f3918fed88c90d
    Signed-off-by: Markos Chandras <mchandras@suse.de>