Update git submodules

Update git submodules

* Update docs/submodules/fuel from branch 'master'
  - Merge "AArch64: Switch to upstream Saltstack repo"
  - AArch64: Switch to upstream Saltstack repo

    To work around the missing dependency of 'python-tornado' on
    'python-features' provided by the binary-specific DEB package
    in amd64 Saltstack repository, pre-install the req explicitly
    on FN (jumpserver) and VCP VMs via lib.sh.

    JIRA: ARMBAND-382

    Change-Id: I2dbd08a58f6cf57c2c48c2d7fc8d19ad4872e800
    Signed-off-by: Alexandru Avadanii <Alexandru.Avadanii@enea.com>