Update git submodules

Update git submodules

* Update docs/submodules/yardstick from branch 'master'
  - Merge "Check RS for virtualized OpenStack/Yardstick"
  - Check RS for virtualized OpenStack/Yardstick

    Draft for env requirements reading and validation
    Script can be run from tools/virt_ci_rampup.sh. First requirement file is
    parsed/stored. This file must be created in ahead and named as
    'infra_deploy.yaml'. Then separate ansible role is used to validate
    resources. Ansible-role fails if there is not enough resources on the host
    for cpu, ram, disk space.

    JIRA: YARDSTICK-945

    Change-Id: I86cd4bdc963de3aa51392fc73a239cbd426bc64a
    Signed-off-by: Stepan Andrushko <stepanx.andrushko@intel.com>