Update git submodules

* Update docs/submodules/releng-xci from branch 'master'
  - Merge "Check if /etc/ssl/certs exists before creating it"
  - Check if /etc/ssl/certs exists before creating it

    In CentOS and Suse, /etc/ssl/certs is a symbolic link to
    /etc/ssl/pki/tls/certs.  The Ansible module "file" will fail if it is asked to
    create a directory which is already a symbolic link.

    This patch will check if /etc/ssl/certs exists before trying to create it.

    The same check is done both on the host and the opnfv guest VM.

    Also, /etc/certs is only writable by root, so we need a "become: true" clause
    to be able to modify it in localhost (but not in opnvf VM).

    Change-Id: Iab6c3c162548f84ad6082829e4a7c2ab63d2cfa0
    Signed-off-by: Tapio Tallgren <tapio.tallgren@nokia.com>

diff --git a/docs/submodules/releng-xci b/docs/submodules/releng-xci
index 07d8817..57fcda3 160000 (submodule)
--- a/docs/submodules/releng-xci
+++ b/docs/submodules/releng-xci
@@ -1 +1 @@
-Subproject commit 07d88170fa827f9907a62d6bdbf3bc0c1ffc90ee
+Subproject commit 57fcda3cebed64bfc1d5f85761cc3f24853641e7