Update git submodules

Update git submodules

* Update cinder from branch 'master'
  to 268db57daaebec682839e20a9ca92d40b2e03c22
  - Merge "api: Merge os-services extension"
  - api: Merge os-services extension

    We no longer want to support enabling and disabling API extensions.
    Start this process by merging in the os-services API. Nothing changes
    yet with regards to configuration but that is coming.

    Note that we can now delete the 'ServiceController.update' method since
    we can use 'mapper.connect' rather than 'mapper.resource'.

    Change-Id: I352488f501c7ebd32f895e59e8d593d73a2d97dc
    Signed-off-by: Stephen Finucane <stephenfin@redhat.com>