Update git submodules

Update git submodules

* Update docs/submodules/edgecloud from branch 'master'
  - Allowing resource optimized OpenStack

    One option for the deployment of edge cloud infrastructures
    is to use different instances of the same resource optimized
    OpenStack in both the large, medium and small edge sites.

    This change adds this as an alternative to the usage of
    different OpenStack deployment variants in the different
    sites.

    Change-Id: Icdcdb7fb8b0cb43f36b2f53ef74278475aa9817e
    Signed-off-by: Gergely Csatari <gergely.csatari@nokia.com>